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ABSTRACT: IEEE 1451 standard is intended to address the smart transducer interfacing problem in network environments. Usually, proprietary hardware and software are a very efficient solution for implementing the aforementioned normative, although they can become expensive and inflexible. In contrast, the use of open and standardized resources for implementing the IEEE 1451 smart transducer interface standards is proposed in this paper. Tools such as Java and Phyton programming languages, Linux, low-cost programmable logic devices, personal computer resources, and Ethernet architecture were integrated to construct a network node based on the IEEE 1451 standard. The node can be used in systems based on the client-server communication model. The evaluation of the employed tools and experimental results are presented.
IEEE Transactions on Instrumentation and Measurement 11/2009; · 1.21 Impact Factor
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ABSTRACT: Piezoelectric transducers are widely used in high-resolution positioning systems. This paper reports the experimental analysis of a novel piezoelectric flextensional actuator (PFA), which is designed by using the topology-optimization method through a low-cost homodyne Michelson interferometer. By applying the J<sub>1</sub>-J<sub>4</sub> method for signal demodulation, which provides a linear and direct measurement of dynamic optical phase shift independent of fading, the nanometric displacements of the PFA were determined. Linearity and frequency response of the PFA were evaluated up to 50 kHz. PFA calibration factor and amplification rate were determined for the PFA operating in the quasi-static regime. To confirm the observed frequencies of resonance, an impedance analyzer is also utilized to measure the magnitude and phase of the PFA admittance
IEEE Transactions on Instrumentation and Measurement 07/2007; · 1.21 Impact Factor
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ABSTRACT: An ultrasonic density-measurement cell is experimentally characterized as a function of temperature. The measurement of propagation velocity and density of several liquids is performed in the 15 degC-40 degC temperature range. Results are compared to the tabulated values in the case of distilled water, showing an accuracy of 0.07% for the propagation velocity. The cell was tested with distilled water, alcohol, and homogenized milk, and density values are compared to those obtained with a pycnometer, showing 0.2% accuracy in density measurement for stabilized temperature and 0.4% accuracy under thermal gradient conditions
IEEE Transactions on Instrumentation and Measurement 07/2007; · 1.21 Impact Factor
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ABSTRACT: Piezoelectric transducers are widely used in high resolution positioning systems, compact ultrasonic motors and vibration suppressors. In this work it is described the experimental characterization of a new flextensional piezoactuator designed by the topology optimization method. Using a homodyne Michelson interferometer and applying the J<sub>1</sub>-J<sub>4</sub> method for signal demodulation, which provides a linear and direct measurement of dynamic optical phase shift independently of fading, the nanometric displacements of points on the piezoactuator surface were determined. Linearity and frequency response of the flextensional piezoactuator were evaluated up to 50 kHz, beyond the first resonance frequency of its PZT-5A piezoceramic. To confirm the observed frequencies of resonance it was also utilized an impedance analyzer to measure the magnitude and phase of the piezoactuator admittance
Instrumentation and Measurement Technology Conference, 2005. IMTC 2005. Proceedings of the IEEE; 06/2005
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[show abstract]
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ABSTRACT: IEEE 1451 standard is intended to address the smart transducer interfacing problematic in network environments. Usually, proprietary hardware and software is a very efficient solution to implement the IEEE 1451 normative, although can be expensive and inflexible. In contrast, the use of open and standardized tools for implementing the IEEE 1451 normative is proposed in this paper. Tools such as Java and Phyton programming languages, Linux, programmable logic technology, personal computer resources and Ethernet architecture were integrated in order to construct a network node based on the IEEE 1451 standards. The node can be applied in systems based on the client-server communication model. The evaluation of the employed tools and experimental results are presented
Instrumentation and Measurement Technology Conference, 2005. IMTC 2005. Proceedings of the IEEE; 06/2005
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ABSTRACT: Temperature plays an important role in any sensor device, because it can affect sensor properties, limiting its accuracy and operation range. At constant temperature, ultrasonic density sensors can reach accuracies of 0.1%. However, temperature fluctuations are expected to exist in an industrial plant, and sensor performance must be studied in the presence of temperature gradients. Each sensor geometry and construction can give rise to different behaviors under temperature gradients, limiting the possible accuracy in density measurements. In this work, an ultrasonic density measurement cell is experimentally characterized and its performance in the presence of temperature gradients is studied in the 15 to 40degC temperature range for several liquids. The propagation velocity can be measured with high accuracy (0.07 %) in a range of temperatures as long as the sample chamber length is corrected. The cell was tested with distilled water, alcohol and other liquids, showing 0.2 % accuracy in density measurement for stabilized temperature and 0.4 % under thermal gradient conditions
Instrumentation and Measurement Technology Conference, 2005. IMTC 2005. Proceedings of the IEEE; 06/2005
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ABSTRACT: The J<sub>1</sub>... J<sub>3</sub> is a recent optical method for linear readout of dynamic phase modulation index in homodyne interferometers. In this work, the J<sub>1</sub>... J<sub>3</sub> method is applied to measure voltage in an optical voltage sensor. Based on the classical J<sub>1</sub>... J<sub>4</sub> method, the J<sub>1</sub>... J<sub>3</sub> technique shows to be more stable to phase drift and simpler for implementation than the original one. The sensor dynamic range is enhanced. The agreement between theoretical and experimental results, based on 1/f noise, is demonstrated.
Microwave and Optoelectronics Conference, 2007. IMOC 2007. SBMO/IEEE MTT-S International;
