Polymeric strain gauges as pressure sensors for microfabricated organ-on-chips

2017 ◽  
Author(s):  
W. F. Quiros-Solano ◽  
N. Gaio ◽  
C. Silvestri ◽  
G. Pandraud ◽  
P. M. Sarro
Keyword(s):  
Pressure Sensors ◽  
Strain Gauges

Development Of PVDF Thick Film Interdigitated Capacitors For Pressure Measurement On Flexible Melinex Substrates

2005 ◽  
Vol 870 ◽  
Author(s):  
Arous Arshak ◽  
Khalil Arshak ◽  
Deirdre Morris ◽  
Olga Korostynska ◽  
Essa Jafer
Keyword(s):  
Polymer Film ◽  
Thick Film ◽  
Pressure Measurement ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Strain Gauges ◽  
Interdigitated Electrodes ◽  
Higher Sensitivity

AbstractIn this work, a PVDF thick film paste was deposited onto interdigitated electrodes to form a capacitor. Two different substrates, alumina and Melinex® were used. Capacitors, fabricated on alumina substrates were tested as strain gauges, and showed a high sensitivity with low hysteresis. Capacitors on Melinex® substrates were tested as pressure sensors by adhering them to planar and cylindrical surfaces and subjecting them to pressures up to 300 kPa. Their sensitivity and hysteresis during cycling were examined and compared. It was found that sensors on cylindrical surfaces showed a higher sensitivity, however the hysteresis was also increased. It is thought that this is due to instabilities in the polymer film, accentuated by stretching of the substrate.

A Novel Technique for Steam Turbine Exhaust Pressure Limitation Using Dynamic Pressure Sensors

2005 ◽  
Vol 219 (9) ◽  
pp. 925-932 ◽  
Author(s):  
M. S. Riaz ◽  
K. J. Barb ◽  
A Engeda
Keyword(s):  
Steam Turbine ◽  
Dynamic Pressure ◽  
Pressure Sensors ◽  
Operating Conditions ◽  
Strain Gauges ◽  
System Response ◽  
Main Concern ◽  
Finite Elements Analysis ◽  
Pressure Transducers ◽  
Last Stage

In this paper, a novel approach is presented to increase the operational flexibility of steam turbines. Exhaust pressure at the exit of the last-stage blades is one of the most important parameters that limit the operation of a steam turbine, especially on days with hot ambient conditions. The main concern in these off-design high-exhaust pressure operating conditions is that it can result in flow separation, which can lead to aeromechanics instabilities and thus to blade failure because of high-cycle fatigue. In the method proposed in this paper, dynamic pressure transducers are placed around the perimeter of the last-stage blade to measure the pressure variations caused by vibrating last-stage blades. This approach, which is applicable to condensing turbines only, will provide increased exhaust pressure limits through realtime monitoring of the pressure signal and thereby enable the power plant to produce more power during times of peak demand. Finite elements analysis was performed to predict the natural frequencies of the row of blades to distinguish between the synchronous and nonsynchronous modes of vibration. Strain gauges were placed on the blades to obtain the experimental frequency information of the system. Response from the dynamic pressure transducers was compared with responses from the strain gauges. An excellent agreement between the two sets of results proved the validity of the proposed method.

A survey of inkjet-printed low-cost sensors

2018 ◽  
Vol 85 (7-8) ◽  
pp. 504-514
Author(s):  
Christoph Beisteiner ◽  
Bernhard G. Zagar
Keyword(s):  
Low Cost ◽  
Pressure Sensors ◽  
Strain Gauges ◽  
Temperature Dependent ◽  
Moulding Process ◽  
Seebeck Coefficients ◽  
Injection Moulding Process ◽  
Inkjet Printers ◽  
Lamination Process ◽  
Pet Films

Abstract Inkjet-printers from the company Epson and others can be used to fabricate low-cost sensors on coated PET films. By using nanoparticle-based dispersions resistive temperature dependent sensors, strain gauges, thermocouples and pressure sensors can be fabricated. For these purposes the gauge factors, Seebeck coefficients and temperature coefficients of resistance for Ag, Carbon Black and PEDOT:PSS dispersions on Mitsubishi® and Pelikan® PET substrates are characterized. Furthermore, piezoresistive effects in transverse and longitudinal strain directions are discussed. Additionally, a printed sensor system for measuring strains within a surface is presented. Finally, an injection-moulding process and a lamination process are used to improve the mechanical scratching of those sensors.

Sensitive Elements of High Temperature Pressure Sensors Formed from a Doped Polycrystalline Diamond

2021 ◽  
Vol 1031 ◽  
pp. 178-183
Author(s):  
Elena Vysotina ◽  
Razhudin Rizakhanov ◽  
Sergey Sigalaev ◽  
Nikolay Polushin ◽  
Vadim Shokorov ◽  
...  
Keyword(s):  
High Temperature ◽  
Diamond Film ◽  
Pressure Sensors ◽  
Polycrystalline Diamond ◽  
Resistance Strain ◽  
Promising Material ◽  
Strain Gauges ◽  
Extreme Conditions ◽  
Boron Doped ◽  
Polycrystalline Diamond Film

The need to create highly accurate pressure sensors that capable operate under extreme conditions in aviation, rocket and space equipment increases and becomes more relevant. The unique properties of diamond make it a promising material for microelectronic sensors. Sensitive elements of pressure sensors were developed where a resilient element is formed from silicon but resistance strain gauges are formed from a boron-doped polycrystalline diamond film.

Nanocomposite Conductive Elastomer: Microfabrication Processes and Applications in Soft-Matter MEMS Sensors

2006 ◽  
Vol 947 ◽  
Author(s):  
Chang Liu
Keyword(s):  
Carbon Nanotube ◽  
Soft Matter ◽  
Pressure Sensors ◽  
Strain Gauges ◽  
Microfluidic Channels ◽  
Mems Sensors ◽  
Structural Applications ◽  
Polydimethylsiloxane Elastomer ◽  
Filled Composite

ABSTRACT3D micro-molded PDMS (polydimethylsiloxane) elastomer is widely used in MEMS. However, traditional PDMS is non-conductive and as a result is used in mostly structural applications. It is difficult to embed elastomeric, “stretchy” conductors and transduction elements in molded PDMS matrix. We report general methods for monolithic fabrication of multi-layer PDMS structures with embedded conductive and non-conductive elastomer elements. Conductive PDMS parts, made of carbon-nanotube-filled composite PDMS, can form internal elastomer wires, electrodes, heaters, and sensors. The process uses a series of PDMS patterning, micromolding, and bonding techniques. In this work we demonstrate elastomer strain gauges, capacitive pressure sensors, as well as microfluidic channels with integrated heaters and sensors.

An Approach on the Use of Co-Sputtered W-DLC Thin Films as Piezoresistive Sensing Materials

2021 ◽  
Vol 14 ◽  
Author(s):  
Gabriela Leal ◽  
Humber Furlan ◽  
Marcos Massi ◽  
Mariana Amorim Fraga
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Synthesis Method ◽  
Pressure Sensors ◽  
Strain Gauges ◽  
Gauge Factor ◽  
Diamond Like Carbon ◽  
Piezoresistive Sensors ◽  
Thin Film Resistors ◽  
Lift Off

Background: Miniaturized piezoresistive sensors, particularly strain gauges, pressure sensors, and accelerometers, have been used for measurements and control applications in various fields, such as automotive, aerospace, industrial, biomedical, sports, and many more. A variety of different materials have been investigated for the development of these sensors. Among them, diamond-like carbon (DLC) thin films have emerged as one of the most promising piezoresistive sensing materials due to their excellent mechanical properties, such as high hardness and high Young’s modulus. At the same time, metal doping has been studied to enhance its electrical properties. Objective: This article explores the use of co-sputtered tungsten-doped diamond-like carbon (W-DLC) thin films as microfabricated strain gauges or piezoresistors. Methods: Different serpentine thin-film resistors were microfabricated on co-sputtered W-DLC thin films using photolithography, metallization, lift-off, and RIE (reactive ion etching) processes. In order to evaluate their piezoresistive sensing performance, gauge factor (GF) measurements were carried out at room temperature using the cantilever beam method. Results: GF values obtained in this study for co-sputtered W-DLC thin films are comparable to those reported for W-DLC films produced and characterized by other techniques, which indicates the feasibility of our approach to use them as sensing materials in piezoresistive sensors. Conclusion: W-DLC thin films produced by the co-magnetron sputtering technique can be considered as sensing materials for miniaturized piezoresistive sensors due to the following key advantages: (i) easy and well-controlled synthesis method, (ii) good piezoresistive properties exhibiting a GF higher than metals, and (iii) thin-film resistors formed by a simple microfabrication process.

scholarly journals Silicon whisker pressure sensors for noise reduction in silencers

2021 ◽  
pp. 28-32
Author(s):  
A. A. Druzhinin ◽  
A. P. Kutrakov ◽  
R. V. Zinko
Keyword(s):  
Noise Suppression ◽  
Combustion Engine ◽  
Pressure Sensors ◽  
Low Frequency ◽  
High Sensitivity ◽  
Strain Gauges ◽  
Active System ◽  
Operating Modes ◽  
Noise Characteristics ◽  
Active Noise

The article contains the results of research and development of a system for active noise damping of an automobile engine. The main source of noise from a running engine is exhaust noise. The frequency spectrum of this sound has a pronounced low-frequency character, which explains its weak absorption when the sound is propagating in open spaces. A possible solution to this problem is to use an active system for suppressing the resonant frequencies of the muffler using strain gauges to read the primary information about the dynamic processes that determine the noise level. It is for such active noise suppression systems that the authors develop a high-temperature pressure sensor based on strain gauges made of silicon whiskers. Such strain gauges have unique mechanical properties, are characterized by high sensitivity and the ability to operate in various amplitude-frequency and temperature ranges up to 500℃. The study of the dynamic characteristics of pressure sensors made it possible to confirm the quality of its electromechanical part and determine that the measurement error of the sensor is ±0.5 in the temperature range of 20 to 500℃. The active noise suppression system is a buffer tank whose volume changes in accordance with signals from pressure sensors. This design makes it possible to dynamically change the resonant frequency of the buffer capacitance depending on the operating modes of the engine, which leads to a decrease in its noise characteristics. Using the developed additional resonator chamber with a variable volume in the exhaust muffler of an internal combustion engine made it possible to reduce resonance phenomena in the zone of low-frequency pulsations of the exhaust gas pressure from 57 to 43 Hz with a frequency drift in the range of 310 to 350 Hz, which significantly improved its noise characteristics.

Sign in / Sign up

Export Citation Format

Share Document