The article describes the process of manufacturing micro-bending sensors from polydimethylsiloxane and the checking of their function on the basis of damping behaviour. We tested three manufactured alternatives and from the results we determined coefficients for the calculation of the mass of weight on the assumption that the level of damping is known. We also tested the micro-bending sensors in practice as a walking detector, we can imagine similar uses for the sensor because it is compact, reliable, simple to produce, resistant to unfavorable conditions and cheap.
Słowa kluczowe: Polydimethylsiloxane (PDMS), sensor, micro-bending, weight, pressure
W artykule opisano konstrukcję czujnika ugięcia wykonanego z polydimethylsiloxanu. Zbadano trzy alternatywne konstrukcje i określono masę obliczeniowoą przy założeniu że poziom tłumienia jest znany. Zbadano też praktyczne zastosowanie czujnika jako detektora kroków.
Keywords: Polydimethylsiloxane (PDMS), czujnik kroków, miokroczujnik ugięcia
Polydimethylsiloxane (PDMS) is a polymeric material on the basis of silicone, which is used in many scientific fields for various applications. One of the key characteristics is the excellent heat resistance of the material, under long term heat exposure PDMS resists temperatures of 200 °C and for short term exposure temperatures up to 350 °C. This is why it is very often used in electronics for pouring plates of wide connectors, transformers, power sources and so on. The authors of publication  concentrate on one concrete type of polydimethylsiloxane identified as Sylgard 184 and check its mechanical characteristics at various hardening temperatures (25 - 200 °C). The results show that the hardening temperature can change certain mechanical characteristics of PDMS. Samples prepared at a hardening temperature of 25 °C showed a hardness value of 43.8 Shore A, whereas samples prepared at a temperature of 200 °C showed a hardness value of 54 Shore A. In the construction of sensors (particularly pressure sensors) this information is very important because the hardness of the material undoubtedly affects the resulting behaviour of the sensor. Publication  describes a magnetic pole sensor which is constructed from two types of PDMS and a multimodal optical fibre with iron nano-particles. The cover of the sensor is formed by hard polydimethylsiloxane and the internal part of the sensor is filled with a soft silicon gel based on PDMS, so that it is possible using a magnetic field to deflect the first optical fibre with the iron nano-particles. The deviation of the optical fibre has an output of lowering the optical performance. A sensor set up like this can detect a magnetic field up to 0.3 T. A slightly altered sensor can also for instance detect vibrations up to 100 Hz, as is shown in publication . A simple form of pressure sensor made from PDMS is shown in publication . When manufacturing the sensor it is very impo [...]
 I. D. Johnston, D. K. McCluskey, C. K. L. Tan, M. C. Tracey, “Mechanical characterization of bulk Sylgard 184 for microfluidics and microengineering,“ Journal of Micromechanics and Microengineering, vol. 24, art. no. 035017, 2014.  J. Jargus, et. al., “Detection of magnetic field with use of optical sensors,“ Proceedings of SPIE - The International Society for Optical Engineering, vol. 10654, art. no. 1065419, 2018.  J. Jargus, et. al., “Proceedings of SPIE - The International Society for Optical Engineering,“ vol. 10654, art. no. 1065418, 2018.  J. Jargus, et. al., “Analysis of using PDMS polymer as the sensors of the pressure or weight,“ Proceedings of SPIE - The International Society for Optical Engineering, vol. 10440, art. no. 104400J, 2017.  H. Gao, et. al., “Highly-sensitive optical fiber temperature sensors based on PDMS/silica hybrid fiber structures,“ Sensors and Actuators, A: Physical, vol. 284, pp. 22-27 , 2018.  Y. Li, et. al., “Optical hydrogen sensor based on PDMS-formed double-C type cavities with embedded Pt-loaded WO3/SiO2,“ Sensors and Actuators, B: Chemical, vol. 276, pp. 23-30, 2018.  J. Nedoma, et. al., Non-invasive fiber optic probe encapsulated into PolyDiMethylSiloxane for measuring respiratory and heart rate of the human body," Advances in Electrical and Electronic Engineering, vol. 15, pp. 93-100, 2017.  M. Fajkus, et. al., “A non-invasive multichannel hybrid fiberoptic sensor system for vital sign monitoring," Sensors (Switzerland), vol. 17, art. no. 111, 2017.  J. Nedoma, et. al., “Encapsulation of FBG sensor into the PDMS and its effect on spectral and temperature characteristics," Advances in Electrical and Electronic Engineering, vol. 14, pp. 460-466, 2016. J. Nedoma, M. Fajkus, V. Vasinek, “Influence of PDMS encapsulation on the sensitivity and frequency range of fiberoptic interferometer," Proceedings of SPIE - The International Society for Optical Engineering, vol. 9994, art. no. 99940P, 2016. 8 PRZEGLĄD ELEKTROTECHNICZNY, ISSN 0033-2097, R. 95 NR 6/2019 M. Fajkus, J. Nedoma, P. Siska, V. Vasinek, “FBG sensor of breathing encapsulated into polydimethylsiloxane," Proceedings of SPIE - The International Society for Optical Engineering, vol. 9994, art. no. 99940N, 2016. C. Y. Chang, et. al., " Flexible Localized Surface Plasmon Resonance Sensor with Metal-Insulator-Metal Nanodisks on PDMS Substrate," Scientific Reports, vol. 8, art. no. 11812, 2018. J. Vitasek, et. al., “Illumination and communication characteristics of white light created by laser excitation of YAG:Ce phosphor powders," Optical Materials, vol. 83, pp. 131-137, 2018. C. W. Sher, et. al., “Large-area, uniform white light LED source on a flexible substrate," Optics Express, vol. 23, art. no. A1167- A1178, 2015. J. Jia, et. al., “Highly Elastic and Flexible Phosphor Film for Flexible LED Lighting and Display Applications," Faguang Xuebao/Chinese Journal of Luminescence, vol. 39, pp. 1493- 1502, 2017. T. Güner, D. Köseoğlu, M. M. Demir, “Multilayer design of hybrid phosphor film for application in LEDs," Optical Materials, vol. 60, pp. 422-430, 2016. H. Y. Lin, et. al., “Large area lighting applications with organic dye embedded flexible film," Proceedings of SPIE - The International Society for Optical Engineering, vol. 9383, art. no. 93830N, 2015. Y. Li, P. Tao, R. W. Siegel, L. S. Schadler, “Multifunctional silicone nanocomposites for advanced LED encapsulation,“ Materials Research Society Symposium Proceedings, vol. 1547, pp. 161-166, 2013. L. C. Chen, W. W. Lin, J. W. Chen, “Fabrication of GaN-Based White Light-Emitting Diodes on Yttrium Aluminum Garnet- Polydimethylsiloxane Flexible Substrates,“ Advances in Materials Science and Engineering, vol. 2015, art. no. 537163, 2015. S. W. Allison, F. Sabri, P. Parajuli, “Exploration of thin polymer films for phosphor thermometry,“ Advances in Technology to Support End User Mission - Proceedings of the 2016 Joint Conference/Symposium of the Society for Machinery Failure Prevention Technology and the International Society of Automation 2016, code 122447, 2016.