Commercial Data Acquisition Board Research Articles

GloveSense: A Hand Gesture Recognition System Based on Inductive Sensing

Gesture recognition, in particular, hand gesture recognition, has received great attention in the field of human-computer interaction. Although several hand gesture recognition designs have been proposed in the past, they still suffer many limitations in practice. Hence, we present a wearable device, called GloveSense, which is made on a regular glove using conductive threads. The system consists of ten coils, with each pair of coils sewn on both sides of each finger and connected in series. To achieve high sensitivity, a data acquisition system is employed in which a tank circuit made of each sewn coil is measured. Since the utilized commercial data acquisition board has limited channels, a switching mechanism is employed to measure some of the extra coils. The utilized switching mechanism reduces the cross-talk effect between the readings. The GloveSense system is tested for recognition of numbers 1 to 10 in American Sign Language. A dataset of 1400 responses is employed along with a machine learning algorithm for gesture recognition. The proposed system demonstrates a high accuracy of 99% and a short recognition time of less than 1 second.

Electromagnetic Induction Imaging at Multiple Depths With a Single Coil

Electromagnetic induction imaging (EII) is an attractive imaging modality due to its contactless operation, low cost, and good penetration depth. To implement real-time imaging, in applications such as object tracking or functional biomedical imaging, fast data acquisition is required. To proceed toward this goal, in this article, we propose the use of a single coil for 3-D EII along with a fast inversion approach. To collect sufficient data that allow 3-D imaging, we propose two approaches: collecting data at multiple coil’s drive current levels and collecting data with multiple tank circuit’s capacitor values. We show that the use of such data when using a single coil allows for 3-D EII. For proof-of-concept experiments, we use a commercial data acquisition board, that is, LDC1614EVM module, and multilayer planar coils made by Texas Instruments.

Characterization of PXI-Based Generators for Impedance Measurement Setups

Multichannel digital sinewave generators play a key role in digital automated impedance bridges. Along with the technological progress in the development of commercial data acquisition (DAQ) boards, which brings with it improvements in their metrological and functional properties, it is possible to realize the DAQ-based high-precision multichannel generators. This paper describes the evaluation of properties of three commercial DAQs, available in the form of PCI eXtensions for Instrumentation modules and working as two-channel generators supervised by software developed by the authors. Due to the fact that the main application area of these generators is digital impedance bridges, this paper presents research results the most relevant for the impedance bridges, i.e., the stability of amplitude ratio and phase difference as well as total harmonic distortion and spurious-free dynamic range. The results and conclusion presented in this paper may be useful when choosing DAQs intended to be used in the multichannel generators.

A DAQ-based sampling wattmeter for IEEE Std. 1459-2010 powers measurements. Uncertainty evaluation in nonsinusoidal conditions

This paper presents the evaluation of the metrological performances of a DAQ-based sampling wattmeter (DAQ-SW) for the measurement of IEEE Std. 1459-2010 power quantities in non-sinusoidal conditions. The instrument makes use of two commercial data acquisition (DAQ) boards, a non-inductive current shunt, a personal computer and a commercial software for data processing. Starting from the results of an experimental characterization of the two instrument channels with non-sinusoidal voltages and currents and a correlation analysis, the combined standard uncertainties of IEEE Std. 1459-2010 quantities are evaluated, following the approach of the ISO Guide to the Expression of Uncertainty in Measurement (GUM).

DAQs-based wattmeters for high accuracy measurements. Comparison with the Italian power primary standard

This paper is focused on the use of data acquisition boards (DAQs) for the development of high accuracy PC-based instruments for the measurements of electrical power. The proposed systems are simple, portable and low cost because they are based on commercial data acquisition boards (DAQs) connected to a common personal computer. Data processing is carried out by a commercial software based on an interpolating windowed FFT. In the paper it is shown how the voltage can be sensed directly, thanks to the DAQ input range, thus avoiding expensive voltage dividers. The set up of the DAQs-based solutions is described and the evaluation of their metrological features is made by means of a comparison with the Italian power primary standard, which was built at INRIM with a complex solution and expensive with two high precision digital voltmeters.

A PC-Based Wattmeter for Accurate Measurements in Sinusoidal and Distorted Conditions: Setup and Experimental Characterization

This paper presents the development of a high-accuracy sampling wattmeter, which can be employed with both sinusoidal and distorted input signals. The proposed personal computer (PC)-based system is a simple, portable, and low-cost solution because it is based on two commercial data acquisition boards connected to a common PC. Owing to this solution, the voltage is sensed directly, avoiding expensive voltage dividers, while the current is sensed by means of a noninductive current shunt. Commercial software is also used for data processing and implementation of the virtual instrument. The setup of the PC-based wattmeter is described, with a detailed description of the correction strategy of systematic contributions to the measurement uncertainty of analog-to-digital converter conversion. An experimental evaluation of its metrological performances is made by means of several experimental tests, with both sinusoidal and distorted voltages and currents, which were carried out with an electric power standard and a high-performance multifunction calibrator.

Automatic Meter for Determination of Solid Semiconductors Conductivity

Conditions and requirements for the measurement of oxide semiconductors conductivity as well as methods and equipments available, are presented in this paper. Reasons are given for the automatic meter designed in this work. Conductivity is determined based on the voltage-current method using a PC and a commercial data acquisition board. The instrument is described mentioning the relevant points considered in the design. The software for the operation of the system is described as well as measurements results obtained in the laboratory on components that emulate the real experiments.

Real-time monitoring and diagnosing in wire-electro discharge machining

This paper presents the design and development of a real-time monitoring and diagnostic system for diagnosing the degraded behaviour in wire-electro discharge machining. The detection in advance of the degraded behaviour is crucial since this can lead to the breakage of the cutting tool (the wire), reducing the process productivity and the required accuracy (Ho et al., Tools Manuf 44:1247–1259, 2004). This work presents the design and development of a real-time monitoring system that alerts the degraded behaviour. It can detect different types of degraded behaviours that have been previously identified during the analysis phase. Unlike other works found in the literature review, which are focussed on proprietary hardware, the present paper proposes a flexible real-time platform based on a commercial data acquisition board that can be easily configured for different purposes. It has been applied to develop a real-time monitoring and diagnostic system that uses virtual sensors to diagnose the degradation of the process. The results of this work show a satisfactory performance of the presented approach.

Development of multiple frequency electromagnetic induction systems for steel flow visualization

This paper presents recent developments in the use of electromagnetic induction tomography (EMT) for steel flow visualization. Several aspects are reported. First, results are shown from an 8-coil, single-frequency, EMT system from tests using liquid steel. The results are consistent with video recordings of an exposed section of the steel flow passing through a submerged entry nozzle, in terms of flow size and position, providing a good representation of the steel flow profile changes during trials. The second part describes the development of a system with a C-shaped sensor, which is capable of being slotted in place for practical deployment as well as being rapidly removed during nozzle changes. The effects of reducing the number of coils in this configuration were also studied. Finally, the development of a multiple-frequency system for plant use is reported. The system is designed based on a commercial data acquisition board, which can provide three sinusoidal signals with target frequencies for excitation simultaneously. This paper describes the new hardware electronics and software. Experimental results show that the system is able to identify a variety of test samples. Instead of imaging the cross-section of the steel flow profiles, the current system is developed for checking signal levels at different operation frequencies, which are of more interest for industrial use. Nevertheless, the work demonstrates a significant step forward to develop a multiple-frequency EMT system for practical use in this industrial process application.

Real-Time Monitoring and Diagnosis Platform for a Machining Process

This paper presents the design and development of a real-time monitoring and diagnosis system for diagnosing degraded cutting regimes in Wire Electrical Discharge Machining (WEDM). The detection in advance of the degradation of the cutting process is crucial since this can lead to the breakage of the cutting tool (the wire), reducing the process productivity and the required accuracy. This work presents the design and development of a real-time monitoring system that alerts of degraded operation. Unlike other works found in the literature review, which are focused on proprietary hardware, the present paper proposes a flexible real-time platform based on a commercial data acquisition board that can be easily configured for different purposes. It has been applied to develop a real-time monitoring and diagnosis system that uses virtual sensors to diagnose the process degradation. The results of this work show a satisfactory performance of the presented approach.

Design of a Virtual-Instrumentation System for a Machining Process

This paper presents a virtual-instrumentation system (VIS) that aims at measuring the evolution of key magnitudes in a nonconventional machining process called wire electrical discharge machining (WEDM). The VIS consists of two well-different parts: the acquisition system that measures process signals (voltage and current) and the virtual measurement of relevant magnitudes (such as energy, peak-current distribution, and ignition delay time). The data-acquisition system provides flexibility and ease of storing tests under different machining conditions without extra hardware construction or adaptation. It is based on a commercial data-acquisition board that works at very high frequencies (up to 10 MSamples/s). The virtual measurement is carried out by modeling and processing the acquired signals. The VIS has been employed to monitor and detect low-quality cutting regimes in WEDM.

Development of an Intergrated System for Electrochemical Detection

There is an increasing interest on research laboratories to employ easy-touse equipments, which should present low fabrication costs. In this work is presented a homemade multipotentiostat that allows the realization of four simultaneous electrochemical analyses. Its sensitivity ranges are: 1 μA/V, 100 μA/V, 10 μA/V, 1 μA/V, and 100 nA/V. The multipotentiostat is portable and uses two nine-volt batteries as power supplies. It was specially designed for voltammetrics analysis (Cyclic Voltammetry, and Differential Pulse Voltammetry), with a user- interface developed in LabVIEWTM v.7.0. The data acquisition and system control are made by a commercial Data Acquisition board (DAC) LabPC+, from National Instruments. Functioning and flexibility were verified using the two voltammetric methods to detect K3Fe(CN)6, a calibration solution. In future works, a self-interface will permit field measurements using PDAs as us er interface.

Hardware and software design for an electromagnetic induction tomography (EMT) system for high contrast metal process applications

This paper presents the latest development of an EMT system designed for use in the metal production industry such as imaging molten steel flow profiles during continuous casting. The system that has been developed is based on a commercial data acquisition board residing in a PC host computer and programmed in the LabView graphical language. The paper reviews the new EMT hardware electronics and software. The noise effects and the detectability limits of the system are given in the paper followed by the system sensitivity map analysis. Optimal image reconstructions, including the simultaneous iterative reconstruction technique (SIRT) and non-iterative Tikhonov regularization, truncated singular value decomposition (TSVD), are also discussed and applied for the system. The system has been demonstrated in real time (10 frames s−1 for 5 kHz excitation) with test phantoms that represent typical metal flow profiles such as central, annular stream and multiple streams.

Suitability study of a histogramming software architecture in the data acquisition system of position sensitive X-ray detectors

We describe here an approach, based on software algorithms and techniques for the histogramming of raw data, to the position encoding in X-ray detectors. This runs on a standard platform and uses a commercial data acquisition board. We also describe the hardware and software set-up, and the results of the tests carried out in order to show its suitability. The results show that: it is possible to achieve a throughput, for a sustained mean event rate, in excess of 3 MHz; the Linux operating system, with an appropriate driver development, is a suitable option, and; it is possible to reach acceptable event throughput, whilst increasing flexibility and reducing the overall cost of the data acquisition system.

Automatic compensation system for impedance measurement

This paper deals with the realization of the four-pair terminal definition of impedance standards. A simple, though reliable, system is described that allows an automatic compensation of the voltage at the low potential port of impedance standards to be obtained. Such a system employs a commercial data acquisition board and a signal generator with adjustable-phase capability, which acts as the phase reference for the generator that feeds the impedance standard. A standard PC controls the whole system and implements the demodulation and the control algorithms. Preliminary tests have been performed in the frequency range of 50 Hz to 20 kHz with different kinds of impedance standards (resistive, inductive and capacitive), obtaining a residual voltage at the low potential port of less than 5 /spl mu/V.

MASTER: a Windows program for recording multiple auditory steady-state responses

MASTER is a Windows-based data acquisition system designed to assess human hearing by recording auditory steady-state responses. The system simultaneously generates multiple amplitude-modulated and/or frequency-modulated auditory stimuli, acquires electrophysiological responses to these stimuli, displays these responses in the frequency-domain, and determines whether or not the responses are significantly larger than background electroencephalographic activity. The operator can print out the results, store the data on disk for more extensive analysis by other programs, review stored data, and combine results. The system design follows clear principles concerning the generation of acoustic signals, the acquisition of artifact-free data, the analysis of electrophysiological responses in the frequency-domain, and the objective detection of signals in noise. The instrument uses a popular programming language (LabVIEW) and a commercial data acquisition board (AT-MIO-16E-10), both of which are available from National Instruments.

New Method for Measuring Statistical Distributions of Partial Discharge Pulses.

A new digital detection system is described for measuring pulsating partial discharges (PDs). The PD detection system can continuously record all PD pulses that occur over extended periods of time, with a minimum inter-pulse time separation of 6 μs and a vertical amplitude resolution of 12 bits. Earlier PD detection systems detected PD pulse amplitude and time using complex custom-designed hardware while the present system continuously records the complete electrical waveform that carries the PD pulses using a commercial data acquisition board and extracts, in real time, the time and amplitude information of all PD pulses in software. The current approach considerably reduces the development and maintenance cost of the PD detection system, significantly increases the system portability, and may prove to be a crucial step for transferring the digital PD detection and analysis technology developed in laboratories to industry. The features of the new system are illustrated by the study of dc-excited PD pulses occurring in a point-to-plane gap in air. A new surface-mediated burst mode of PDs is discovered in which a PD pulse has a certain probability to induce another pulse. The probability is determined for several gap voltages and is found to vary strongly with the applied voltage.

An electrical impedance tomography measurement system for experimental use

In electrical impedance tomography (EIT) currents are applied into a volume through electrodes and the resulting voltages at the electrodes are measured. The impedance distribution inside the volume can then be calculated by solving the associated inverse problem. Usually the equipment that is needed for the generation of the current patterns and the measurements are large, expensive and tailored to specific situations. In such cases many of the measurement parameters are fixed and the user cannot change these to adapt the equipment to another measurement situation. In this article we present a simple and affordable EIT measurement device that is based on a PC computer, commercial data acquisition board and software and an external current generation and switching board. We also verify the performance and applicability of the system with a phantom measurement and an unusual measurement object for which there is no specific equipment, that is, the measurement of internal impedance distribution of spruce logs.

A hardware-independent data acquisition package incorporating a simulation driver and simulation description language

Device drivers for commercial data acquisition boards (DASH-16, DT2801) and a device driver for a virtual data acquisition board have been developed and incorporated in a single package for a multiple station anesthesia research laboratory. The package provides a compiler for a simulation description language which is used to program the virtual board. The package, written in C for the IBM PC, was designed to be easily extended with additional drivers. Applications using the package can control all supported devices without the programmer having to learn the details of the hardware.