Simple Electronic Interface Research Articles

Minimizing the wiring in distributed strain sensing using a capacitive sensor sheet with variable-resistance electrodes

Strain mapping over a large area usually requires an array of sensors, necessitating extensive and complex wiring. Our solution is based on creating multiple sensing regions within the area of a single capacitive sensor body by considering the sensor as an analogical transmission line, reducing the connections to only two wires and simplifying the electronic interface. We demonstrate the technology by using piezoresistive electrodes in a parallel plate capacitor that create varying proportions of electromagnetic wave dissipation through the sensor length according to the interrogation frequency. We demonstrate, by a sensor divided into four virtual zones, that our cracked capacitive sensor can simultaneously record strain in each separated zone by measuring the sensor capacitance at a high frequency. Moreover, we confirm that by changing the frequency from high to low, our sensor is able to measure the local strain amplitudes. This sensor is unique in its ability to monitor strain continuously over a large area with promoted spatial resolution. This sensing technology with a reduced number of wires and a simple electronic interface will increase the reliability of sensing while reducing its cost and complexity.

Development of automated spray pyrolysis setup for chemical vapour deposition like growth of thin solid films

This paper presents a simple electronic interface for spray pyrolysis to deposit high quality thin solid films. The exhibited electronic circuit with the Arduino based microcontroller is acting as the interface between the primary process parameters and the computer running National Instruments{®} LabVIEW{®}. The proposed setup and deposition flow achieve a reproducible, repeatable, and uniform deposition of thin films through the spray pyrolysis technique, which improves the conventional spray pyrolysis technique. The conventional spray nozzle was replaced by the therapeutic aerosol nebulizer, a cost viable replacement, for uniform, smooth, chemical vapor deposition (CVD)-like deposition. The efficacy of the automated nebulizer spray pyrolysis (n-SP) setup was demonstrated by depositing fluorine doped tin oxide (SnO2:F), zinc oxide (ZnO) and zinc sulfide (ZnS) thin films and also by comparing the characterization results of the films with the literature. Results suggest that the proposed automated nebulizer spray pyrolysis setup has the ability to change the commercial production of device quality thin films from complex chemical vapor deposition to cost-effective, simple and automated nebulizer spray pyrolysis method.

Recent developments on application of nanometal-oxide based gas sensor arrays

It is shown that the sensor arrays can acquire more information on a given sample than an individual sensor. The main classes of gas-sensing materials include metal-oxide semiconductors. Gas sensors based on chemiresistive semiconducting metal-oxides have many potential benefits including, their very low cost, fast response, recovery time, simple electronic interface, ease of use, and ability to detect a large analytes. Recent advances in gas sensor arrays have shown the capability to incorporate nanomaterial based cross-reactive array. In this way it is possible to increase the surface/volume ratio of the sensing layer. Therefore the surface scattering is better influenced by adsorbed species and change in sensor conductivity is higher. Also the sensitivity of semiconductor oxide materials can be improved by using of nanoparticles. Gas sensor arrays based on nanotechnology can rapidly, sensitively, and selectively detect target molecules.

Pt- and Pd-nanoclusters functionalized carbon nanotubes networked films for sub-ppm gas sensors

A gas chemiresistor, fabricated onto alumina using multi-walled carbon nanotubes (MWCNTs) networked films grown by radiofrequency plasma enhanced chemical vapor deposition (RF-PECVD) technology, is described for high-performance gas detection, at an operating temperature of 200 °C. Functionalizations of MWCNTs tangled bundle-films with nominally 5-nm thick Pt- and Pd-nanoclusters, prepared by magnetron sputtering, provide higher sensitivity for significantly enhanced gas detection of NO2, H2S, NH3, CO, up to a low limit of sub-ppm level. The measured electrical conductance of the functionalized MWCNTs upon gas exposures is modulated by charge transfer with p-type semiconducting characteristics. Pt- and Pd-nanoclusters functionalized MWCNTs gas sensors exhibited better performances compared to unfunctionalized MWCNTs, making them promising candidates for air-pollutants environmental monitoring. Simple electronic interface for the chemiresistor has been developed with a voltage output of the sensor signal.

A simple device and a project for the nonlinear control systems laboratory

This paper describes a new inverted pendulum system that is useful to illustrate important aspects of nonlinear control systems theory. The stabilization of the pendulum is to be achieved by the on-off action of two electromagnets; therefore, an adequate switching policy has to be applied. The pendulum can be controlled by a computer, using simple electronic interface circuits. This paper considers first an example from literature that suggests some design principles about the new system. Second, there is a detailed description of the pendulum. Finally, the use of the system in a student's project is presented. The experimental device is easy to build, inexpensive, and has good pedagogical impact.

A Pulse Amperometric Sensor for the Measurement of Atmospheric Hydrogen Peroxide

Gaseous H(2)O(2) is sampled through a Nafion membrane diffusion scrubber while 1 mM HCl is maintained stationary in the scrubber. After a preselected preconcentration time (typically, 5-10 min), a valve is opened to allow the scrubber liquid to flow by gravity over an electrochemical H(2)O(2) sensor for a brief period. The miniature flow-over sensor consists of a Pt/Rh wire working electrode and a Pt wire counter electrode wound respectively on separate segments of a Nafion solid polymer electrolyte tubing supported on a Ag/AgCl wire reference electrode. A simple electronic interface and a personal computer are used to control and record the electrochemical measurement. The liquid phase detection limit for this sensor is ∼30 nM H(2)O(2) in the anodic oxidation mode. For a 9 min gas sample preconcentration period, the LOD (S/N = 3 criterion) is 0.11 ppbv H(2)O(2)(g). Ambient H(2)O(2) data obtained with this instrument were in excellent agreement with those obtained by an established fluorometric technique in a blind intercomparison.

A simple electronic interface for wireless chemical data communications

91. Bits and pieces, 37. A brief note on a simple electronic interface for wireless chemical data communications.