Статті в журналах: "Long range displacement sensor"

1

Alonso-Murias, Monserrat C., David Monzón-Hernández, Osvaldo Rodríguez-Quiroz, J. Enrique Antonio-Lopez, Axel Schülzgen, Rodrigo Amezcua-Correa, and Joel Villatoro. "Long-range multicore optical fiber displacement sensor." Optics Letters 46, no. 9 (April 30, 2021): 2224. http://dx.doi.org/10.1364/ol.421004.

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2

Xue, Songtao, Kang Jiang, Shuai Guan, Liyu Xie, Guochun Wan, and Chunfeng Wan. "Long-Range Displacement Meters Based on Chipped Circular Patch Antenna." Sensors 20, no. 17 (August 28, 2020): 4884. http://dx.doi.org/10.3390/s20174884.

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This paper presents a passive wireless long-range displacement sensor that is based on the circular patch antenna, and the detecting range of the sensor can be customized. The sensor consists of a chipped circular antenna with two opened rectangular windows, a substrate, and a ground plate with a sloping channel. No bonding between the antenna and the ground plate allows for the chipped antenna to slide along the sloping channel. The channel will drive the current flow on the plate once the chip is activated, increasing the effective electrical length and, consequently, decreasing the resonant frequency of the circular antenna. The sensing mechanism equates the measuring displacement to the relative movement of the antenna with respect to the ground that achieves the measurement of long-range displacement and, thus, the proposed sensor can avoid stress damage to the antenna due to excessive deformation. Three different range sensors were simulated in the the Ansoft high frequency structure simulator (HFSS). The results show that the resonance frequency of the antenna has a linear relationship with the varying chute depth beneath the chip. Three sensors were fabricated, and the experimental results also validated that the sensitivity of the sensor can be adjusted.

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3

Khiat, Ali. "Silicon grating microfabrication for long-range displacement sensor." Journal of Micro/Nanolithography, MEMS, and MOEMS 7, no. 2 (April 1, 2008): 021007. http://dx.doi.org/10.1117/1.2909459.

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4

Bonse, M. H. W., F. Zhu, and H. F. van Beek. "A long-range capacitive displacement sensor having micrometre resolution." Measurement Science and Technology 4, no. 8 (August 1, 1993): 801–7. http://dx.doi.org/10.1088/0957-0233/4/8/001.

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5

Thomas, Jineesh, T. R. Rajanna, and Sundarrajan Asokan. "Temperature Compensated FBG Displacement Sensor for Long-Range Applications." IEEE Sensors Letters 4, no. 1 (January 2020): 1–4. http://dx.doi.org/10.1109/lsens.2019.2959377.

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6

Hu, Ye, Qian Hui Zhao, Yong Ming Chen, and Lei Wang. "A Simple and Long-Range Displacement Measurement System." Applied Mechanics and Materials 341-342 (July 2013): 839–42. http://dx.doi.org/10.4028/www.scientific.net/amm.341-342.839.

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This paper introduces a well-used long range displacement measurement system. The advantages of the system are that the sensor's measurement range can be extended by optical linear scale with a simple structure, and the distance between the measured object and the sensor can be automatically adjusted. The feasibility of the measurement system is tested by simulation experiments, and the accuracy performance is evaluated with respect to both repeatability error and linearity error. The experimental results show that the displacement measurement system reaches a level of accuracy which is sufficient for operational requirements.

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7

Yu, Jian-ping, Wen Wang, Ke-qing Lu, De-qing Mei, and Zi-chen Chen. "A planar capacitive sensor for 2D long-range displacement measurement." Journal of Zhejiang University SCIENCE C 14, no. 4 (April 2013): 252–57. http://dx.doi.org/10.1631/jzus.c12mnt03.

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8

Liu, Rong Xian, Yong Fa Qin, and Fan Li. "The Research of the Shock Angular Displacement Sensor." Applied Mechanics and Materials 427-429 (September 2013): 1060–63. http://dx.doi.org/10.4028/www.scientific.net/amm.427-429.1060.

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Impact resistance angular displacement sensors are widely used in motion mechanical system, which not only requires the sensor having the advantages of large measurement range, long life, also the sensor need to withstand shock and vibration. We use the finite element analysis on the key structure of the sensor and design the sensor circuit.. The sensor has the advantages of high strength shell and flexible packaging, and it can withstand the impact of the gravitational acceleration 100g on three directions.

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9

Kim, Moo-Jin, and Won-Kyu Moon. "A new capacitive displacement sensor for high accuracy and long range." Journal of Sensor Science and Technology 14, no. 4 (July 30, 2005): 219–24. http://dx.doi.org/10.5369/jsst.2005.14.4.219.

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10

Kim, Moojin, Wonkyu Moon, Euisung Yoon, and Kwang-Ryeol Lee. "A new capacitive displacement sensor with high accuracy and long-range." Sensors and Actuators A: Physical 130-131 (August 2006): 135–41. http://dx.doi.org/10.1016/j.sna.2005.12.012.

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11

Liu, Xiaokang, Kai Peng, Ziran Chen, Hongji Pu, and Zhicheng Yu. "A New Capacitive Displacement Sensor With Nanometer Accuracy and Long Range." IEEE Sensors Journal 16, no. 8 (April 2016): 2306–16. http://dx.doi.org/10.1109/jsen.2016.2521681.

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12

Arifin, A., A. M. Hatta, Sekartedjo, M. S. Muntini, and A. Rubiyanto. "Long-range displacement sensor based on SMS fiber structure and OTDR." Photonic Sensors 5, no. 2 (February 7, 2015): 166–71. http://dx.doi.org/10.1007/s13320-015-0225-4.

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13

Yu, Haoyu, Xiaolong Chen, Jinsong Zhan, and Zhaoxiang Chen. "A Long-Range High Applicability Length Comparator for Linear Displacement Sensor Calibration." IEEE Transactions on Instrumentation and Measurement 70 (2021): 1–10. http://dx.doi.org/10.1109/tim.2020.3011795.

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14

Hong, Yifan, Ryo Sato, Yuki Shimizu, Hiraku Matsukuma, and Wei Gao. "A New Optical Configuration for the Surface Encoder with an Expanded Z-Directional Measuring Range." Sensors 22, no. 8 (April 14, 2022): 3010. http://dx.doi.org/10.3390/s22083010.

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This paper proposes a new optical configuration for a two-axis surface encoder that can measure the in-plane (X-axis) and out-of-plane (Z-axis) displacements of a positioning stage. The two-axis surface encoder is composed of a scale grating and a sensor head. A transparent grating is employed in the sensor head for measurement of the Z-directional displacement of the scale grating based on the Fizeau-type measurement method; a reference beam reflected from the transparent grating and the zeroth-order diffracted beam from the scale grating are superimposed to generate an interference signal. A pair of prisms and a beam splitter are also employed in the sensor head, so that the positive and negative first-order diffracted beams can be superimposed over a long working distance to generate an interference signal for measurement of the X-directional displacement of the scale grating. Focusing on the new, extended Z-directional measurement mechanism, proof-of-principle experiments were carried out to verify the feasibility of the proposed optical configuration for the surface encoder that can measure the uni-directional displacements of a scale grating along the X- and Z-axis. Experimental results from the developed optical configuration demonstrated the achievement of a Z-directional measuring range of ±1.5 mm.

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15

Fukushige, Takashi, Takehiko Hayashi, Seiichi Hata, and Akira Shimokohbe. "Built-in Capacitive Displacement Sensor with Long Full-Scale Range for Electrostatic Microactuators." IEEJ Transactions on Sensors and Micromachines 126, no. 9 (2006): 522–27. http://dx.doi.org/10.1541/ieejsmas.126.522.

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16

Chen, Ziran, Hongji Pu, Xiaokang Liu, Donglin Peng, and Zhicheng Yu. "A Time-Grating Sensor for Displacement Measurement With Long Range and Nanometer Accuracy." IEEE Transactions on Instrumentation and Measurement 64, no. 11 (November 2015): 3105–15. http://dx.doi.org/10.1109/tim.2015.2437633.

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17

Jeong, D. H., Hyun Kyu Kweon, and Y. S. Kim. "Development of the Precision Stage with Nanometer Accuracy and a Millimeter Dynamic Range." Key Engineering Materials 381-382 (June 2008): 47–48. http://dx.doi.org/10.4028/www.scientific.net/kem.381-382.47.

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Most of the nano-positioning systems(stage) are accomplished by a flexure hinge mechanism, which is two or three multilayer PZT actuators to realize the high accuracy and long range[1]. In this paper, it can be made by a new nano stage with the bending characteristics of the mechanical cantilever that is composed of the step motor, one multilayer PZT actuator and the displacement sensor unit. The sensor unit consists of semiconductor LD, PD and sensor holder. The displacement of stage is acquired by the bending control of the cantilever between the step motor and the PZT actuator. The basic properties of the positioning stage are presented. From these results, we can know that the new nano stage can be made by only one multilayer PZT actuator .

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18

Krakover, Naftaly, B. Robert Ilic, and Slava Krylov. "Micromechanical resonant cantilever sensors actuated by fringing electrostatic fields." Journal of Micromechanics and Microengineering 32, no. 5 (March 17, 2022): 054001. http://dx.doi.org/10.1088/1361-6439/ac5a61.

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Abstract We report on the architecture and operational principle of a resonant cantilever-type displacement sensor. The device is actuated electrostatically by a side electrode that is coplanar with the cantilever and by a gap-closing electrode positioned underneath the beam. The unique electrode geometry combined with the appropriate actuating voltages allows positioning of the cantilever in close proximity to the bistability threshold, where the frequency sensitivity to the electrode displacement is enhanced. Using a reduced order model backed by numerical simulations, the dependencies of the device frequency on the beam’s deflections and the actuation voltages were mapped. We show wide-range tunability that spans a range between softening and hardening behavior. We demonstrate displacement sensing using fabricated single crystal silicon ≈2000 µm long, ≈5 µm thick cantilevers. When compared to a resonant cantilever sensor actuated solely by a gap-closing electrode, measurements from our fringing field actuated devices show a four times higher sensitivity of ≈98 Hz µm−1. The suggested approach may find applications in a broad range of micro and potentially nano-scale applications including resonant inertial, force, mass and bio-sensors.

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19

Zhang, Hong, You Ping Liu, Jian Hua Li, and Mao Dong Xiong. "The Study and Applications on Fiber Bragg Grating (FBG) Monitoring System for Deep and Large Deformed Soft Ground." Advanced Materials Research 261-263 (May 2011): 1341–47. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.1341.

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The fiber Bragg grating (FBG) technology is studied based on the current monitoring status of the highway soft ground settlement, for instance, the low degree of automation, the unsatisfied accuracy of the device, the slow data transmission and the greater measurement errors. The limited measuring range and the difficult situations of the soft ground burying and installing of the fiber optic sensor still need to be addressed. This thesis has analyzed the development of the long range optical fiber displacement sensor as well as its burying techniques which are suitable for soft ground settlement monitoring. Both of them have been successfully applied to De Chang Highway D10 subject. The study also shows that the long range optical fiber displacement sensor is able to meet the requirements of the soft ground monitoring. And data can be accurately monitored by means of real-time or on-line continuously. This is of great significance in pushing forward the development of the fiber optical monitoring technology in the field.

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20

Prelle, Christine, Frédéric Lamarque, and Philippe Revel. "Reflective optical sensor for long-range and high-resolution displacements." Sensors and Actuators A: Physical 127, no. 1 (February 2006): 139–46. http://dx.doi.org/10.1016/j.sna.2005.11.005.

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21

Xue, Songtao, Zhiquan Zheng, Shuai Guan, Liyu Xie, Guochun Wan, and Chunfeng Wan. "A Capacitively-Fed Inverted-F Antenna for Displacement Detection in Structural Health Monitoring." Sensors 20, no. 18 (September 17, 2020): 5310. http://dx.doi.org/10.3390/s20185310.

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This paper presents a capacitive displacement sensor based on a capacitively fed inverted-F antenna (CFIFA) for displacement detection. The sensor is composed of a grounded L-shape patch and a rectangular upper patch, forming a capacitor between them. The asymmetric dipole model is adopted to explain the frequency shift and current distribution of the proposed antenna sensor at its first-order resonance. The numerical simulation of the CFIFA using the Ansoft high-frequency structure simulator (HFSS) software is carried out to optimize the dimensional parameters, allowing the antenna to perform better. Two sets of CFIFAs are fabricated and tested for verification. Results show that the CFIFA has a good linear relationship between its first resonant frequency and the relative displacement, and is capable of a long range of displacement measuring.

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22

Yu, Zhicheng, Kai Peng, Xiaokang Liu, Hongji Pu, and Ziran Chen. "A new capacitive long-range displacement nanometer sensor with differential sensing structure based on time-grating." Measurement Science and Technology 29, no. 5 (April 10, 2018): 054009. http://dx.doi.org/10.1088/1361-6501/aaaf05.

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23

Cheong, Yong Moo, Shin Kim, and Hyun Kyu Jung. "Application of Magnetostrictive Transducer for the Long-Range Guided Wave Inspection." Key Engineering Materials 345-346 (August 2007): 1295–98. http://dx.doi.org/10.4028/www.scientific.net/kem.345-346.1295.

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The leakage of the pipes is a major issue for the safety of industrial structures. However, in many cases, because of their geometrical complexity and inaccessibility, it is difficult to inspect them by the conventional NDE method. A long-range guided wave inspection, thus, is an option to inspect them. A torsional vibration mode, T(0,1) shows many advantages in a long-range guided wave examination of a pipe, such as no dispersion characteristic, no radial displacement and low attenuation. However, it is not easy to fabricate a transducer with an array of piezoelectric elements for generation of torsional vibration mode and even expensive. Recently a magnetostrictive metal strip sensor was used for a generation of the torsional vibration modes in a pipe and this technique has shown several advantages for practical applications. This study investigated the applicability of a long-rang guided ultrasonic method to the detection of artificial notches even in the presence of various foreign objects.

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24

Peng, Kai, Xiaokang Liu, Ziran Chen, Zhicheng Yu, and Hongji Pu. "Sensing Mechanism and Error Analysis of a Capacitive Long-Range Displacement Nanometer Sensor Based on Time Grating." IEEE Sensors Journal 17, no. 6 (March 15, 2017): 1596–607. http://dx.doi.org/10.1109/jsen.2017.2654500.

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25

Dahmen, Nikolaj, Roland Hohensinn, and John Clinton. "Comparison and Combination of GNSS and Strong-Motion Observations: A Case Study of the 2016 Mw 7.0 Kumamoto Earthquake." Bulletin of the Seismological Society of America 110, no. 6 (August 18, 2020): 2647–60. http://dx.doi.org/10.1785/0120200135.

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ABSTRACT The 2016 Mw 7.0 Kumamoto earthquake resulted in exceptional datasets of Global Navigation Satellite Systems (GNSS) and seismic data. We explore the spatial similarity of the signals and investigate procedures for combining collocated sensor data. GNSS enables the direct observation of the long-period ground displacements, limited by noise levels in regimes of millimeters to several centimeters. Strong-motion accelerometers are inertial sensors and therefore optimally resolve middle- to high-frequency strong ground motion. The double integration from acceleration to displacement amplifies long-period errors introduced by tilt, rotation, noise, and nonlinear instrument responses and can lead to large nonphysical drifts. For the case study of the Kumamoto earthquake, 39 GNSS stations (1 samples/s) with nearby located strong-motion accelerometers (100 samples/s) are investigated. The GNSS waveforms obtained by precise point positioning under real-time conditions prove to be very similar to the postprocessed result. Real-time GNSS and nearby located accelerometers show consistent observations for periods between ∼3–5 and ∼50–100 s. The matching frequency range is defined by the long-period noise of the accelerometer and the low signal-to-noise ratio (SNR) of GNSS, when it comes to small displacements close to its noise level. Current procedures in fusing the data with a Kalman filter are verified for the dataset of this event. Combined data result in a very broadband waveform that covers the optimal frequency range of each sensor. We explore how to integrate fused processing in a real-time network, including event detection and magnitude estimation. Carrying out a statistical test on the GNSS records allows us to identify seismic events and sort out stations with a low SNR, which would otherwise impair the quality of downstream products. The results of this study reinforce the emerging consensus that there is real benefit to collocation GNSS and strong-motion sensors for the monitoring of moderate-to-large earthquakes.

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26

Monzel, Christian, and Gottfried Unden. "Transmembrane signaling in the sensor kinase DcuS ofEscherichia coli: A long-range piston-type displacement of transmembrane helix 2." Proceedings of the National Academy of Sciences 112, no. 35 (August 17, 2015): 11042–47. http://dx.doi.org/10.1073/pnas.1507217112.

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The C4-dicarboxylate sensor kinase DcuS is membrane integral because of the transmembrane (TM) helices TM1 and TM2. Fumarate-induced movement of the helices was probed in vivo by Cys accessibility scanning at the membrane–water interfaces after activation of DcuS by fumarate at the periplasmic binding site. TM1 was inserted with amino acid residues 21–41 in the membrane in both the fumarate-activated (ON) and inactive (OFF) states. In contrast, TM2 was inserted with residues 181–201 in the OFF state and residues 185–205 in the ON state. Replacement of Trp 185 by an Arg residue caused displacement of TM2 toward the outside of the membrane and a concomitant induction of the ON state. Results from Cys cross-linking of TM2/TM2′ in the DcuS homodimer excluded rotation; thus, data from accessibility changes of TM2 upon activation, either by ligand binding or by mutation of TM2, and cross-linking of TM2 and the connected region in the periplasm suggest a piston-type shift of TM2 by four residues to the periplasm upon activation (or fumarate binding). This mode of function is supported by the suggestion from energetic calculations of two preferred positions for TM2 insertion in the membrane. The shift of TM2 by four residues (or 4–6 Å) toward the periplasm upon activation is complementary to the periplasmic displacement of 3–4 Å of the C-terminal part of the periplasmic ligand-binding domain upon ligand occupancy in the citrate-binding domain in the homologous CitA sensor kinase.

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27

Liu, Xiaokang, Hui Zhang, Kai Peng, Qifu Tang, and Ziran Chen. "A High Precision Capacitive Linear Displacement Sensor with Time-Grating that Provides Absolute Positioning Capability Based on a Vernier-Type Structure." Applied Sciences 8, no. 12 (November 28, 2018): 2419. http://dx.doi.org/10.3390/app8122419.

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Nanometer-scale measurement devices with high accuracy and absolute long-range positioning capability are increasingly demanded in the field of computer numerical control machining. To meet this demand, the present report proposes a capacitive absolute linear displacement sensor with time-grating that employs a vernier-type structure based on a previously proposed single-row capacitive sensing structure. The novel proposed vernier-type absolute time-grating (VATG) sensor employs two capacitor rows, each with an equivalent measurement range. The first capacitor row is designed with n periods to realize fine measurement, while the second capacitor row is designed with n − 1 periods, and the phase difference between the second row and the first row is employed to obtain absolute positioning information. A prototype VATG sensor with a total measurement range of 600 mm and n = 150 is fabricated using printed circuit board manufacturing technology, and its measurement performance is evaluated experimentally. Harmonic analysis demonstrates that the measurement error mainly consists of first-harmonic error, which is mostly caused by signal crosstalk. Accordingly, an optimized prototype VATG sensor is fabricated by adding a shielding layer between the two capacitor rows and designing a differential induction structure. Experimental results demonstrate that the measurement error of the optimized prototype sensor is ±1.25 μm over the full 600 mm range and ±0.25 μm over a single 4 mm period.

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28

Lim, Jae-In, Seung-Hwan Kim, Seoung-Hun Lee, Hae-Won Jeong, Min-Hee Lee, Shung-Whan Kim, and Kyong-Hon Kim. "Optical System Design and Experimental Demonstration of Long-range Reflective-type Precision Displacement Sensors." Korean Journal of Optics and Photonics 22, no. 3 (June 25, 2011): 151–58. http://dx.doi.org/10.3807/kjop.2011.22.3.151.

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29

Rasouli, Saifollah, and Mostafa Shahmohammadi. "Portable and long-range displacement and vibration sensor that chases moving moiré fringes using the three-point intensity detection method." OSA Continuum 1, no. 3 (November 12, 2018): 1012. http://dx.doi.org/10.1364/osac.1.001012.

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30

Li, Jicheng, H. Neumann, and R. Ramalingam. "Design, fabrication, and testing of fiber Bragg grating sensors for cryogenic long-range displacement measurement." Cryogenics 68 (June 2015): 36–43. http://dx.doi.org/10.1016/j.cryogenics.2015.02.002.

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31

Kirschel, Alexander N. G., Nathalie Seddon, and Joseph A. Tobias. "Range-wide spatial mapping reveals convergent character displacement of bird song." Proceedings of the Royal Society B: Biological Sciences 286, no. 1902 (May 2019): 20190443. http://dx.doi.org/10.1098/rspb.2019.0443.

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A long-held view in evolutionary biology is that character displacement generates divergent phenotypes in closely related coexisting species to avoid the costs of hybridization or ecological competition, whereas an alternative possibility is that signals of dominance or aggression may instead converge to facilitate coexistence among ecological competitors. Although this counterintuitive process—termed convergent agonistic character displacement—is supported by recent theoretical and empirical studies, the extent to which it drives spatial patterns of trait evolution at continental scales remains unclear. By modelling the variation in song structure of two ecologically similar species of Hypocnemis antbird across western Amazonia, we show that their territorial signals converge such that trait similarity peaks in the sympatric zone, where intense interspecific territoriality between these taxa has previously been demonstrated. We also use remote sensing data to show that signal convergence is not explained by environmental gradients and is thus unlikely to evolve by sensory drive (i.e. acoustic adaptation to the sound transmission properties of habitats). Our results suggest that agonistic character displacement driven by interspecific competition can generate spatial patterns opposite to those predicted by classic character displacement theory, and highlight the potential role of social selection in shaping geographical variation in signal phenotypes of ecological competitors.

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32

Sokol-Kutylovskii, Oleg. "Nonlinear amplification of the magnetic induction signal in a magnetomodulation sensor with an amorphous ferromagnetic core." Izvestiya VUZ. Applied Nonlinear Dynamics 30, no. 2 (March 31, 2022): 233–38. http://dx.doi.org/10.18500/0869-6632-2022-30-2-233-238.

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The purpose of this work is to show the possibility of using a magnetic field-controlled nonlinearity of the amplitude change in an oscillatory LC-circuit containing a core made of an amorphous ferromagnetic alloy with compensated longitudinal magnetostriction, which makes it possible to obtain a high conversion coefficient of weak magnetic field sensors operating at room temperature. Methods. A practical method for constructing magnetomodulation sensors of magnetic induction with a fixed magnetic displacement field, which corresponds to the maximum steepness of the nonlinear characteristic of an oscillatory circuit with an amorphous ferromagnetic core in the region of autoparametric resonance, is considered. Results. It has been shown that the stable conversion factor of a 35 mm long sensor based on an oscillatory circuit with autoparametric amplification at a modulation frequency of 256 kHz can reach 10 mV/nT, which allows, with the available element base, to record signals of a weak alternating magnetic field with an amplitude of 0.03 pT/Hz1/2 in the frequency range 10...1000 Hz. It is noted that the excitation of the sensor by a weak harmonic magnetic field of a high frequency and the constant presence of the amorphous ferromagnetic core near the state of technical saturation significantly reduces the level of intrinsic magnetic noise of the magnetomodulation sensor. Conclusion. Magnetomodulation sensors with autoparametric amplification of the magnetic induction signal can find application in geophysics, magnetobiology and biomedicine.

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33

Al-Handarish, Yousef, Olatunji Mumini Omisore, Jing Chen, Xiuqi Cao, Toluwanimi Oluwadara Akinyemi, Yan Yan, and Lei Wang. "A Hybrid Microstructure Piezoresistive Sensor with Machine Learning Approach for Gesture Recognition." Applied Sciences 11, no. 16 (August 6, 2021): 7264. http://dx.doi.org/10.3390/app11167264.

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Developments in flexible electronics have adopted various approaches which have enhanced the applicability of human–machine interface fields. Recently, microstructural integration and hybrid functional materials were designed for realizing human somatosensory. Nonetheless, designing tactile sensors with smart structures using facile and low-cost fabrication processes remains challenging. Furthermore, using the sensors for recognizing stimuli and feedback applications remains poorly validated. In this study, a highly flexible piezoresistive tactile sensor was developed by homogeneously dispersing carbon black (CB) in a microstructure porous sugar/PDMS-based sponge. Owning to its high flexibility and softness, the sensor can be mounted on human or robotic systems for different clinical applications. We validated the applicability of the proposed sensor by applying it to recognizing grasp and release forces in an open setting and to classifying hand motions that surgeons apply on the master interface of a robotic system during intravascular catheterization. For this purpose, we implemented the long short-term memory (LSTM)-dense classification model and five traditional machine learning methods, namely, support vector machine, multilayer perceptron, decision tree, and k-nearest neighbor. The models were used to classify the different hand gestures obtained in an open-setting experiment. Amongst all, the LSTM-dense method yielded the highest overall recognition accuracy (87.38%). Nevertheless, the performance of the other models was in a similar range, showing that our sensor structure can be applied in intelligence sensing or tactile feedback systems. Secondly, the sensor prototype was applied to analyze the motions made while manipulating an interventional robot. We analyzed the displacement and velocity of the master interface during typical axial (push/pull) and radial operations with the robot. The results obtained show that the sensor is capable of recording unique patterns during different operations. Thus, a combination of the flexible wearable sensors and machine learning could yield a future generation of flexible materials and artificial intelligence of things (AIoT) devices.

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Ngeljaratan, Luna, and Mohamed A. Moustafa. "Implementation and Evaluation of Vision-Based Sensor Image Compression for Close-Range Photogrammetry and Structural Health Monitoring." Sensors 20, no. 23 (November 30, 2020): 6844. http://dx.doi.org/10.3390/s20236844.

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Much research is still underway to achieve long-term and real-time monitoring using data from vision-based sensors. A major challenge is handling and processing enormous amount of data and images for either image storage, data transfer, or image analysis. To help address this challenge, this study explores and proposes image compression techniques using non-adaptive linear interpolation and wavelet transform algorithms. The effect and implication of image compression are investigated in the close-range photogrammetry as well as in realistic structural health monitoring applications. For this purpose, images and results from three different laboratory experiments and three different structures are utilized. The first experiment uses optical targets attached to a sliding bar that is displaced by a standard one-inch steel block. The effect of image compression in the photogrammetry is discussed and the monitoring accuracy is assessed by comparing the one-inch value with the measurement from the optical targets. The second application is a continuous static test of a small-scale rigid structure, and the last application is from a seismic shake table test of a full-scale 3-story building tested at E-Defense in Japan. These tests aimed at assessing the static and dynamic response measurement accuracy of vision-based sensors when images are highly compressed. The results show successful and promising application of image compression for photogrammetry and structural health monitoring. The study also identifies best methods and algorithms where effective compression ratios up to 20 times, with respect to original data size, can be applied and still maintain displacement measurement accuracy.

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35

Lu, Hong, S. C. Choi, S. M. Lee, C. H. Park, and D. W. Lee. "Development of a Magnified Mechanism for Fast Tool Servo System." Key Engineering Materials 516 (June 2012): 317–20. http://dx.doi.org/10.4028/www.scientific.net/kem.516.317.

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Flexure-hinge mechanisms are commonly used in the design of translational micro/nanopositioning stages. They can offer a drive system with negligible friction and no need for lubrication. Usually, a large motion range requires the use of a very long actuator which could interfere with a tight workplace. A lever which amplifies the input motion of a short actuator is an effective technique to solve the problem. This paper presents the methodology for the design of a lever-type magnified flexure mechanism used for the ultra precision fast tool servo (FTS) system. A lever type hinge mechanism is designed and utilized to guide the tool holder and to preload the PZT actuator. A low capacitance PZT actuator is adopted to match the given amplifier to achieve optimum performance of device displacement. A high resolution capacitive sensor is utilized to measure the natural displacement of the tool holder. An amplifier with a multiplying factor of 12 is utilized to magnify the drive signal for the expansion and retraction of the PZT actuator. Meanwhile, the motion range of the FTS system can reach up to 98.12 μm with a primary resonant frequency of about 460 Hz, and the amplification of the lever flexure mechanism is approximately 5 as calculated from the experiment.

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36

Shimizu, Hiroki, Takahiro Akiyoshi, Shinya Yanagihara, Yuuma Tamaru, and Akiyoshi Baba. "A Novel MEMS Device for Scanning Profile Measurement with Three Cantilever Displacement Sensors." Applied Mechanics and Materials 870 (September 2017): 237–42. http://dx.doi.org/10.4028/www.scientific.net/amm.870.237.

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A novel Micro Electro Mechanical System (MEMS) measurement device for straightness measurement with a three point method has been proposed. This device integrates three cantilever displacement sensors with a narrow pitch on a silicon chip. The authors determine appropriates shape, dimensions of the cantilever, and a fabrication process. According to simulation results, a triangular cantilever with altitude 12 mm long, base 4mm long, and 0.25 mm thickness was adopted to realize the target measuring range of 100 μm. Near the end of each cantilever, a square frustum probe 250 μm high which was fabricated by anisotropic wet etching was placed. Near the base of cantilevers, four piezo resistance gauges were formed; two are active gauges for measuring stress arise from a displacement at the probe and the others are dummy gauges for temperature compensation. Wiring and contact terminals were fabricated on the base substrate and the total size of the device is 20 mm × 32 mm. The fabrication process of this device was designed and result of a trial production was reported.

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37

Jolliff, Jason K., M. David Lewis, Sherwin Ladner, and Richard L. Crout. "Observing the Ocean Submesoscale with Enhanced-Color GOES-ABI Visible Band Data." Sensors 19, no. 18 (September 10, 2019): 3900. http://dx.doi.org/10.3390/s19183900.

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Ocean color remote sensing has long been utilized as a fundamental research tool in the oceanographic investigations of coupled biological-physical processes. Despite numerous technical advances in the application of space borne ocean-viewing radiometers, host satellite platforms in a polar-orbiting configuration often render the temporal frequency of sensor data acquisition insufficient for studies of ocean processes that occur within increasingly smaller space-time scales. Whereas geostationary ocean color missions are presently the exception (GOCI) rather than the rule, this paper presents a method to convolve ocean reflectance data obtained from contemporary ocean-viewing multispectral radiometers (VIIRS, OLCI) with spectrally-limited Advanced Baseline Imager (ABI) data obtained from the GOES-R meteorological satellites. The method, Chromatic Domain Mapping (CDM), employs a colorimetry approach to visible range ocean reflectance data. The true color space is used as a frame-of-reference that is mapped by the dedicated yet temporally sparse ocean color sensors; coincident and spectrally coarse information from ABI is then used to estimate the evolution of the true color scene. The procedure results in very high resolution (~5 min) true color image sequences. Herein, example CDM applications of rapid frontal boundary evolution and feature displacement in the Gulf of Mexico are presented and future applications of this technique are discussed.

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38

Kuras, Przemysław, Łukasz Ortyl, Tomasz Owerko, Marek Salamak, and Piotr Łaziński. "GB-SAR in the Diagnosis of Critical City Infrastructure—A Case Study of a Load Test on the Long Tram Extradosed Bridge." Remote Sensing 12, no. 20 (October 15, 2020): 3361. http://dx.doi.org/10.3390/rs12203361.

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This article describes a case of using remote sensing during a static load test of a large bridge, which, because of its location, belongs to a critical city infrastructure. The bridge in question is the longest tram flyover in Poland. This is an extradosed-type concrete structure. It conducts a long tram line over 21 other active lines of an important railway station in the center of Cracow. The diagnostic of such bridges involving the load test method is difficult. Traditional, contact measurements of span displacements are not enough anymore. In such cases, remote sensing becomes an indispensable solution. This publication presents an example of using the close-range radar remote sensing technique of ground-based radar interferometry. However, the cross-sections of the huge bridge were observed using several methods. The aim was to confirm the conditions and efficiency of radar displacement measurements. They were therefore traditional contact measurements using mechanic sensors conducted, if possible, to the bottom of the span, for precise leveling and measurement using electronic total station. Comparing the results as well as the discussion held demonstrated the fundamental advantages of remote sensing methods over the other more traditional techniques.

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39

Anstis, Stuart M., and George Mather. "Effects of Luminance and Contrast on Direction of Ambiguous Apparent Motion." Perception 14, no. 2 (April 1985): 167–79. http://dx.doi.org/10.1068/p140167.

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A study is reported of the role of luminance and contrast in resolving ambiguous apparent motion (AM). Different results were obtained for the short-range (SR) and the long-range (LR) motion-detecting processes. For short-range jumps (7.5 min arc), the direction of ambiguous AM depended on brightness polarity, with AM only from white to white and from black to black. But for larger jumps, or when an interstimulus interval (ISI) was introduced, AM was less dependent on polarity, with white often jumping to black and black jumping to white. Two potential AMs were pitted against each other, one carried by a light stimulus and the other by a dark stimulus. The stimulus whose luminance differed most from the uniform surround captured the AM. Visual response to luminance was linear, not logarithmic. When the stimulus was modified to give continuous AM in one direction it was followed by a negative aftereffect of motion only when the spatial displacement was 1 min arc. A larger displacement (10 min arc) gave good AM but no motion aftereffect. Thus only short-range motion adapts motion-sensitive channels.

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40

Daul, Lars, Tao Jin, Ingo Busch, and Ludger Koenders. "Influence of Geometric Properties of Capacitive Sensors on Slope Error and Nonlinearity of Displacement Measurements." Sensors 21, no. 13 (June 22, 2021): 4270. http://dx.doi.org/10.3390/s21134270.

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Capacitive sensors are widely used in industrial applications, such as CNC machine tools, where reliable positioning in the micrometer range with nanometer accuracy is required. Hence, these sensors are operated in harsh industrial environments. The accuracy of these sensors is mainly limited by slope errors and nonlinearities. In practice, the required accuracy of these sensors is achieved by a calibration against a metrological high-quality reference such as interferometric displacement measurement systems. This usually involves the use of high-order polynomials as calibration functions based on empirical data. In metrology, this is only the second-best approach and has disadvantages in terms of stability over the measurement range of the instrument. In addition, the validity of these empirical calibrations over time is questionable, and the associated uncertainty can only be roughly estimated. This makes regular recalibration of such sensors at short intervals mandatory to ensure the reliability of the displacement measurement. In this paper, we report on our investigations of the different parameters that affect the accuracy of capacitive sensors. Since the capacitance of these sensors results from the electric fields that build up between the electrodes, these field lines are calculated using FEM simulation models for typical commercial sensors. In the following the influence of various geometric parameters such as edge radius, guard ring size and shape, or thickness of the electrodes are individually analyzed according to their impact on the accuracy of these sensors. Based on these simulations, the deviations of the capacitance as they arise for real detector geometries can then be compared with idealized, de facto unrealizable parallel plate capacitors. This methodology allows overall uncertainty of capacitive sensors to be decomposed into their individual components and sorted in terms of their contribution to the uncertainty budget. The individual FEM-based analysis then enables a systematic analysis of the sources of uncertainty and, thus, reveals possibilities to improve manufacturing processes for capacitive sensors, to put these sensors on a solid metrological basis, and to improve the performance of these displacement measurement systems in the long run, i.e., to provide better sensors for the application.

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41

Chen, Chia-Wei, Matthias Hartrumpf, Thomas Längle, and Jürgen Beyerer. "Sensitivity enhanced roll-angle sensor by means of a quarter-waveplate." tm - Technisches Messen 88, s1 (August 24, 2021): s48—s52. http://dx.doi.org/10.1515/teme-2021-0069.

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Abstract Attitude metrology (roll, pitch, and yaw) plays an important role in many different fields. Roll angle is considered the most difficult measurement quantity in angular displacements compared to pitch and yaw angles because the rotation axis of the roll angle is parallel to the probe beam. In this work, a sensitivity enhanced roll-angle sensor is presented. The principle is based on the polarization change of a sensing unit (quarter-waveplate). The polarization model is analyzed by Mueller matrix formalism. The Stokes parameters are detected by a Stokes polarimeter. The novel coaxial design improves the sensitivity and reduce the complexity of optical system alignment by means of a fixed quarter-waveplate. The proposed sensor provides a simple setup to measure roll angles with a high sensitivity of 0.006∘ and a long unambiguous measurement range of 180∘.

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42

Wang, Shutang, Minghui He, Bingjuan Weng, Lihui Gan, Yingru Zhao, Ning Li, and Yannan Xie. "Stretchable and Wearable Triboelectric Nanogenerator Based on Kinesio Tape for Self-Powered Human Motion Sensing." Nanomaterials 8, no. 9 (August 24, 2018): 657. http://dx.doi.org/10.3390/nano8090657.

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Recently, wearable, self-powered, active human motion sensors have attracted a great deal of attention for biomechanics, physiology, kinesiology, and entertainment. Although some progress has been achieved, new types of stretchable and wearable devices are urgently required to promote the practical application. In this article, targeted at self-powered active human motion sensing, a stretchable, flexible, and wearable triboelectric nanogenerator based on kinesio tapes (KT-TENG) haven been designed and investigated systematically. The device can effectively work during stretching or bending. Both the short-circuit transferred charge and open-circuit voltage exhibit an excellent linear relationship with the stretched displacements and bending angles, enabling its application as a wearable self-powered sensor for real-time human motion monitoring, like knee joint bending and human gestures. Moreover, the KT-TENG shows good stability and durability for long-term operation. Compared with the previous works, the KT-TENG without a macro-scale air gap inside, or stretchable triboelectric layers, possesses various advantages, such as simple fabrication, compact structure, superior flexibility and stability, excellent conformable contact with skin, and wide-range selection of triboelectric materials. This work provides a new prospect for a wearable, self-powered, active human motion sensor and has numerous potential applications in the fields of healthcare monitoring, human-machine interfacing, and prosthesis developing.

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43

Omidalizarandi, M., I. Neumann, E. Kemkes, B. Kargoll, D. Diener, J. Rüffer, and J. A. Paffenholz. "MEMS BASED BRIDGE MONITORING SUPPORTED BY IMAGE-ASSISTED TOTAL STATION." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W18 (October 18, 2019): 833–42. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w18-833-2019.

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Abstract. In this study, the feasibility of Micro-Electro-Mechanical System (MEMS) accelerometers and an image-assisted total station (IATS) for short- and long-term deformation monitoring of bridge structures is investigated. The MEMS sensors of type BNO055 from Bosch as part of a geo-sensor network are mounted at different positions of the bridge structure. In order to degrade the impact of systematic errors on the acceleration measurements, the deterministic calibration parameters are determined for fixed positions using a KUKA youBot in a climate chamber over certain temperature ranges. The measured acceleration data, with a sampling frequency of 100 Hz, yields accurate estimates of the modal parameters over short time intervals but suffer from accuracy degradation for absolute position estimates with time. To overcome this problem, video frames of a passive target, attached in the vicinity of one of the MEMS sensors, are captured from an embedded on-axis telescope camera of the IATS of type Leica Nova MS50 MultiStation with a practical sampling frequency of 10 Hz. To identify the modal parameters such as eigenfrequencies and modal damping for both acceleration and displacement time series, a damped harmonic oscillation model is employed together with an autoregressive (AR) model of coloured measurement noise. The AR model is solved by means of a generalized expectation maximization (GEM) algorithm. Subsequently, the estimated model parameters from the IATS are used for coordinate updates of the MEMS sensor within a Kalman filter approach. The experiment was performed for a synthetic bridge and the analysis shows an accuracy level of sub-millimetre for amplitudes and much better than 0.1 Hz for the frequencies.

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44

Her, Shiuh Chuan, and Bo Ren Yao. "Stress Analysis of Optical Fiber Sensor Embedded Composite Subjected to Tri-Axial Normal Loadings." Key Engineering Materials 364-366 (December 2007): 998–1002. http://dx.doi.org/10.4028/www.scientific.net/kem.364-366.998.

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Optical fiber sensors have been developed during the past decade to measure a wide range of physical quantities such as strain and temperature. The perturbation of the surrounding field in the host due to the presence of the optical sensor will not only alter the values of the field variables being measured, but may also affect the integrity of the host. Resulting degradations can compromise the accuracy and long term reliability of the smart structure. The present paper focuses the attention on constitutent interaction between the optical fiber, coating, matrix and host material. An analytical model to predict the stress fields in the vicinity of the embedded optical fiber was derived. The theoretical development was based on the four concentric cylinders models which represented the optical fiber, protective coating, matrix and host material, respectively. The interfaces between each constitutent were assumed to be perfect bonds, so that the tractions and displacements were continuous across each interface. In this investigation, the host structure was subjected to three normal loadings along the axial directions. Numerical examples were presented to investigate the effects of the coating and host material on the stress distribution in the vicinity of the embedded optical fiber.

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45

Ding, Guo Qing, Xin Chen, Hong Wang, Li Hua Lei, and Yuan Li. "Quantitative Analysis of Lateral Setting Error in Two-Point Method." Advanced Materials Research 690-693 (May 2013): 3235–39. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.3235.

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In a multiple probes scanning system for a high precision straightness measurement, the lateral setting error between probes is ignored generally due to the average effect in the range of the aperture of the probes. In this paper, we study a two displacement sensors scanning system. Firstly, the principle of two-point method which is based on the natural extension method is introduced. Then, the influence of the lateral setting error between two probes is analyzed quantificationally when the discrete Fourier transform algorithm is applied. It is shown that a relative evaluation error within the range of 1% can be obtained if the lateral setting error is smaller than 1.5% of the sampling interval as long as the spatial wavelength of the evaluated profile is longer than the probe interval. The effectiveness of the results of the quantitative analysis is confirmed by computer simulations.

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46

Hu, Jie, Zhongli Wu, Xiongzhen Qin, Huangzheng Geng, and Zhangbin Gao. "An Extended Kalman Filter and Back Propagation Neural Network Algorithm Positioning Method Based on Anti-lock Brake Sensor and Global Navigation Satellite System Information." Sensors 18, no. 9 (August 21, 2018): 2753. http://dx.doi.org/10.3390/s18092753.

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Telematics box (T-Box) chip-level Global Navigation Satellite System (GNSS) receiver modules usually suffer from GNSS information failure or noise in urban environments. In order to resolve this issue, this paper presents a real-time positioning method for Extended Kalman Filter (EKF) and Back Propagation Neural Network (BPNN) algorithms based on Antilock Brake System (ABS) sensor and GNSS information. Experiments were performed using an assembly in the vehicle with a T-Box. The T-Box firstly use automotive kinematical Pre-EKF to fuse the four wheel speed, yaw rate and steering wheel angle data from the ABS sensor to obtain a more accurate vehicle speed and heading angle velocity. In order to reduce the noise of the GNSS information, After-EKF fusion vehicle speed, heading angle velocity and GNSS data were used and low-noise positioning data were obtained. The heading angle speed error is extracted as target and part of low-noise positioning data were used as input for training a BPNN model. When the positioning is invalid, the well-trained BPNN corrected heading angle velocity output and vehicle speed add the synthesized relative displacement to the previous absolute position to realize a new position. With the data of high-precision real-time kinematic differential positioning equipment as the reference, the use of the dual EKF can reduce the noise range of GNSS information and concentrate good-positioning signals of the road within 5 m (i.e. the positioning status is valid). When the GNSS information was shielded (making the positioning status invalid), and the previous data was regarded as a training sample, it is found that the vehicle achieved 15 minutes position without GNSS information on the recycling line. The results indicated this new position method can reduce the vehicle positioning noise when GNSS information is valid and determine the position during long periods of invalid GNSS information.

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47

Föhn, Paul M. B., Christian Camponovo, and Georges Krüsi. "Mechanical and structural properties of weak snow layers measured in situ." Annals of Glaciology 26 (1998): 1–6. http://dx.doi.org/10.3189/1998aog26-1-1-6.

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Weak layers such as buried surface hoar or depth hoar frequently form the failure plane of slab avalanches. Therefore, the mechanical properties of such layers in relation to their snow structure have been investigated. Since it is difficult to transport samples containing a weak layer into cold rooms, the mechanical measurements have to be made in situ.We investigate strain-rate dependency of shear strength by measuring concurrently strength, deformation and acceleration, using a digital force gauge attached to a 0.05 m2 shear frame to which an accelerometer and a displacement sensor are fixed. In doing so, a dynamic force comparable to a driving skier is applied. The measurements cover a strain-rate range 10-2 to 1 s-1. The samples fail in a brittle manner. The shear-strength values cover the range 0.2–2.8 kPa. The dataset is also used to approximate the coefficient G, the shear modulus, for different weak layers.The snow structure has been analysed macroscopically in the field and for some layers representative snow samples have been extracted in order to prepare, in the cold laboratory, single-sided serial planes with cuts every 0.1 mm recorded by video. The analysis of these snow samples should have given the relation between some mechanical properties (strength, strain) and the structural properties. Due to basic problems in defining the connection between complex snow grains (e.g. surface hoar), we were unable to complete this part in due time. Only preliminary results on this aspect are presented here. Based on our long-term database, containing macroscopic structural and strength data of weak layers, a relationship between snow type and shear strength has been established.

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48

Föhn, Paul M. B., Christian Camponovo, and Georges Krüsi. "Mechanical and structural properties of weak snow layers measured in situ." Annals of Glaciology 26 (1998): 1–6. http://dx.doi.org/10.1017/s0260305500014440.

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Анотація:

Weak layers such as buried surface hoar or depth hoar frequently form the failure plane of slab avalanches. Therefore, the mechanical properties of such layers in relation to their snow structure have been investigated. Since it is difficult to transport samples containing a weak layer into cold rooms, the mechanical measurements have to be made in situ. We investigate strain-rate dependency of shear strength by measuring concurrently strength, deformation and acceleration, using a digital force gauge attached to a 0.05 m2 shear frame to which an accelerometer and a displacement sensor are fixed. In doing so, a dynamic force comparable to a driving skier is applied. The measurements cover a strain-rate range 10-2 to 1 s-1. The samples fail in a brittle manner. The shear-strength values cover the range 0.2–2.8 kPa. The dataset is also used to approximate the coefficient G, the shear modulus, for different weak layers. The snow structure has been analysed macroscopically in the field and for some layers representative snow samples have been extracted in order to prepare, in the cold laboratory, single-sided serial planes with cuts every 0.1 mm recorded by video. The analysis of these snow samples should have given the relation between some mechanical properties (strength, strain) and the structural properties. Due to basic problems in defining the connection between complex snow grains (e.g. surface hoar), we were unable to complete this part in due time. Only preliminary results on this aspect are presented here. Based on our long-term database, containing macroscopic structural and strength data of weak layers, a relationship between snow type and shear strength has been established.

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49

Lucas, Carlos, Daniel Hernández-Sosa, David Greiner, Aleš Zamuda, and Rui Caldeira. "An Approach to Multi-Objective Path Planning Optimization for Underwater Gliders." Sensors 19, no. 24 (December 13, 2019): 5506. http://dx.doi.org/10.3390/s19245506.

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Underwater gliders are energy-efficient vehicles that rely on changes in buoyancy in order to convert up and down movement into forward displacement. These vehicles are conceived as multi-sensor platforms, and can be used to collect ocean data for long periods in wide range areas. This endurance is achieved at the cost of low speed, which requires extensive planning to ensure vehicle safety and mission success, particularly when dealing with strong ocean currents. As gliders are often involved on missions that pursue multiple objectives (track events, reach a target point, avoid obstacles, sample specified areas, save energy), path planning requires a way to deal with several constraints at the same time; this makes glider path planning a multi-objective (MO) optimization problem. In this work, we analyse the usage of the non-dominated sorting genetic algorithm II (NSGA-II) to tackle a MO glider path planning application on a complex environment integrating 3D and time varying ocean currents. Multiple experiments using a glider kinematic simulator coupled with NSGA-II, combining different control parameters were carried out, to find the best parameter configuration that provided suitable paths for the desired mission. Ultimately, the system described in this work was able to optimize multi-objective trajectories, providing non dominated solutions. Such a planning tool could be of great interest in real mission planning, to assist glider pilots in selecting the most convenient paths for the vehicle, taking into account ocean forecasts and particular characteristics of the deployment location.

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50

Milenkovic, Nevena, Christiane Wetzel, Rabih Moshourab, and Gary R. Lewin. "Speed and Temperature Dependences of Mechanotransduction in Afferent Fibers Recorded From the Mouse Saphenous Nerve." Journal of Neurophysiology 100, no. 5 (November 2008): 2771–83. http://dx.doi.org/10.1152/jn.90799.2008.

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Here we have systematically characterized the stimulus response properties of mechanosensitive sensory fibers in the mouse saphenous nerve. We tested mechanoreceptors and nociceptors with defined displacement stimuli of varying amplitude and velocity. For each sensory afferent investigated we measured the mechanical latency, which is the delay between the onset of a ramp displacement and the first evoked spike, corrected for conduction delay. Mechanical latency plotted as a function of stimulus strength was very characteristic for each receptor type and was very short for rapidly adapting mechanoreceptors (<11 ms) but very long in myelinated and unmyelinated nociceptors (49–114 ms). Increasing the stimulus speed decreased mechanical latency in all receptor types with the notable exception of C-fiber nociceptors, in which mean mechanical latency was not reduced ≲100 ms, even with very fast ramp stimuli (2,945 μm/s). We examined stimulus response functions and mechanical latency at two different temperatures (24 and 32°C) and found that stimulus response properties of almost all mechanoreceptors were not altered in this range. A notable exception to this rule was found for C-fibers in which mechanical latency was substantially increased and stimulus response functions decreased at lower temperatures. We calculated Q10 values for mechanical latency in C-fibers to be 5.1; in contrast, the Q10 value for conduction velocity for the same fibers was 1.4. Finally, we examined the effects of short-term inflammation (2–6 h) induced by carrageenan on nociceptor and mechanoreceptor sensitivity. We did not detect robust changes in mechanical latency or stimulus response functions after inflammation that might have reflected mechanical sensitization under the conditions tested.

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