Graphical Programming Language LabVIEW Research Articles

Incremental Encoder Speed Acquisition Using an STM32 Microcontroller and NI ELVIS.

Precise motor control requires high accuracy of the rotor position through the incremental encoder. The speed and accuracy of the acquisition equipment (microcontroller) play an important element in terms of cost and efficiency. In this paper, the author presents alternative methods for speed acquisition from an incremental encoder. In the first stage of research, the main performances of the STM32 microcontroller, connected with an incremental encoder, will be analyzed and compared with two different acquisition systems, i.e., ELVIS II and a Unidrive M701 power inverter. Using the LabVIEW graphical programming language, a user-friendly, convenient, and flexible human–machine interface is designed. Due to the advantages provided by the STM32 microcontroller in terms of processing power, cost, and programming interface, the obtained results are accurate and consistent. Through experimental testing and analysis, the speed acquisition is stable for both developed software algorithms used for ELVIS II and STM32 platforms. It is the aim of the paper to propose a useful speed acquisition tool in low-cost, high-accuracy prototyping applications.

FPGA Design of a High- Resolution FIR Band-Pass Filter by Using LabVIEW Environment

Designers regularly use Finite Impulse Response (FIR) filters to fulfil the need for current electronic design applications such as signal or image processing and digital communications because of the remarkable selectivity computational efficiency. Fast and efficient information processing requires a dedicated microprocessor or a digital signal processor that may not always be available or provide enough performance. In such scenarios, designers can configure FPGAs for processing digitized signals. One of the most popular signal processing applications is filtering. Unlike the Infinite Impulse Response (IIR) filters, FIR filters do not have analog equivalent circuits. For this purpose, continuous time-discrete time conversion is not possible with the help of transforms. Because analog filters cannot have a finite impulse response, the design methods of FIR filters can be made as windowing method, pulse response truncation, and optimal filter design method. Considering this information, it aims to digitally separate two signals with different frequencies (2.4 kHz and 4.2 kHz), which are given to the input as analog, to obtain the desired information signal and suppress other signals. We preferred to use LabVIEW graphical programming language to get the digital FIR filter coefficients. We selected rectangular windowing, set the digital filter's sampling frequency as 18720 Hz, and determined the filter's coefficient with high-frequency resolution as 24. Using filter coefficients in the real-time FPGA-VHDL environment, we showed the performance and resource consumption. LabVIEW is used for simulation as well as obtaining filter coefficients. In addition, we compared both simulation and real-time FPGA-VHDL application output waveforms and examined both platforms' advantages and disadvantages.

Експериментална валидација на виртуелен инструмент за мониторинг на квалитет на електрична енергија)

This paper deals with experimental validation of a Virtual Instrument used for power quality monitoring. The Virtual Instrument is developed in the graphical programming language LabVIEW developed by National Instruments and uses specialized signal conditioning circuits and data acquisition card to perform the measurements. LabVIEW greatly enhances the power quality monitoring capabilities because of the short development time, easy creation of a user interface, high sampling rates. All of these factors makes virtual instrumentations more acceptable than classic power quality monitoring instruments. The main goal of this paper is to compare the developed virtual instrument with a power quality analyzer, Fluke 435. Also the uncertainty budgets for DC and AC voltages are evaluated for the virtual instrument. As a referent unit in the uncertainty budget evaluation the calibration Fluke 5500 A is used. From the obtained result the Virtual Instrument showed great capabilities for power quality monitoring

Study for monitoring of the insulation stator winding of the hydro generators using a data acquisition system

The paper presents a study for a system for data acquisition in order to monitor online the state of the insulation stator winding of hydro generators, using the LabVIEW graphical programming language. The data acquisition system allows the acquisition of the quantities of interest in the process and at the same time, through it, the creation of a strong database for the current state of the hydro generator insulation.

Two-channel acoustic noise control system

The results of the development and experimental verification of a two-channel acoustic noise control data processing system that provides real-time control of non-deterministic broadband acoustic noise are presented. The system is implemented using the LabView graphical programming language G. The length of the measured realization is determined by the sample size ratio to the sampling frequency, and the number of measurements of each sound signal is determined by the ratio of the analysis time to the length of the measured realization. The measured realization of the audio signal in the form of 40,000 16-bit binary numbers is processed using the fast Fourier transform. As a result of processing, a discrete audio signal spectrum is obtained in the range from 0 to 20 KHz in steps of 1 Hz. To check the quality of the system’s functioning, a pair of microphone capsules of the MDN-318, wm61, etc. types, widely used in computer audio equipment, preliminarily selected according to the amplitude-frequency characteristics. The results of system verification using a laboratory acoustic chamber are presented. The advantage of the system is the receipt of a difference spectrum of controlled signals. The conclusion is drawn about the possibility of using this system for a qualitative assessment of changes in the noise level along the propagation path, as well as additions to the results of measurements performed by standard methods.

Fragment Velocity Test System Based on PVDF

In order to solve the problem of low measurement accuracy, large environmental interference and high cost of production in fragment velocity test, this paper proposed the fragment velocity test system by using PVDF piezoelectric film, NI-PXI platform and LabVIEW graphical programming language. The test system mainly includes PVDF film, adjusting circuit, acquisition module and terminal control software. The adjusting circuit amplifies the weak signal of the PVDF sensor. The acquisition module is responsible for reading the data collected by the data acquisition card for subsequent analysis and storage. The terminal control software executes data multi-channel acquisition, storage and display. The test system is stable and reliable with high accuracy through experimental verification.

Isothermal Vapor–Liquid Equilibrium Measurements for Alcohol + Water/n-Hexane Azeotropic Systems Using Both Dynamic and Automated Static-Synthetic Methods

Isothermal vapor–liquid equilibrium measurements (pressure– temperature–liquid and vapor composition) were conducted for water (1) + propan-1-ol (2), n-hexane (1) + butan-2-ol (2), and n-hexane (1) + 2-methyl-propan-1-ol (2) at three temperatures, each using a dynamic moderate pressure equilibrium still. Additionally, pressure–temperature-overall composition measurements for the first two systems were conducted for the intermediate temperatures using a newly automated static-synthetic apparatus to confirm the operability of the automation scheme and to compare the model predictions of the vapor-phase compositions from the processed pressure–temperature–liquid composition data by the static-synthetic method with the experimental vapor compositions measured by the dynamic method. The automation scheme was developed and implemented on the original static total pressure vapor–liquid equilibrium apparatus of Raal et al. (Fluid Phase Equilib. 2011, 310, 156–165) using the LabVIEW graphical programming language. In comparison to the manual operating mode, this scheme improved the efficiency of operation by reducing the man-hours involved and minimized the associated uncertainty with the measurement procedure with respect to liquid composition. Once executed, the control scheme requires approximately 2 days to produce a single 40-data point (pressure–temperature–liquid composition) isotherm and minimizes human intervention to 2–3 h in comparison to a 2-week long measurement procedure in the nonautomated operating mode and in excess of 3 weeks using the dynamic method with analysis by gas chromatography. All experimental data were modeled using the γ–Φ approach with the NRTL and UNIQUAC activity coefficient models and the virial equation of state with the Hayden and O’Connell correlation. For the pressure–temperature–liquid and vapor composition data measured, thermodynamic consistency testing was performed. The data sets passed the point test with 0.01 tolerance and the area test with 10% tolerance. Experimental vapor-phase compositions obtained by phase sampling in the dynamic method compared reasonably well with the predictions from the pressure–temperature–liquid composition data measured by the automated static-synthetic method.

Software Design of a Railway Signal Monitoring System based on Optical Fiber Sensing

The current railway track circuit monitoring system is prone to disturbances that can result in accidents. Meanwhile, basic signaling equipment is slow and cannot achieve satisfactory real-time data acquisition speed. This study aims to solve the aforementioned problems by designing an online monitoring and management platform for railway signal infrastructure, which is based on the graphical programming language LabVIEW. Online monitoring and management of railways’ basic signaling equipment allow real-time collection and communication of various signal equipment data. These processes also enable signal processing, chart display, acousto-optic alarm, user authority management, data storage, data query analysis, and report printing. The test results show that the LabVIEW-based basic signaling equipment for monitoring and managing railway systems can transmit data correctly and steadily, thereby resulting in convenient and ideal operation.

A Real Time Control System Simulation Model Based on LabVIEW Graphical Programming Language

A Real Time Control System Simulation Model Based on LabVIEW Graphical Programming Language - written by M. Ahmed And H. S. Taha , A. Saaid And M. Tarek published on 2018/05/18 download full article with reference data and citations

Design of a software for calculating isoelectric point of a polypeptide according to their net charge using the graphical programming language LabVIEW.

A software to calculate the net charge and to predict the isoelectric point (pI) of a polypeptide is developed in this work using the graphical programming language LabVIEW. Through this instrument the net charges of the ionizable residues of the polypeptide chains of the proteins are calculated at different pH values, tabulated, pI is predicted and an Excel (-xls) type file is generated. In this work, the experimental values of the pIs (pI) of different proteins are compared with the values of the pIs (pI) calculated graphically, achieving a correlation coefficient (R) of 0.934746 which represents a good reliability for a p < 0.01. In this way the generated program can constitute an instrument applicable in the laboratory, facilitating the calculation to graduate students and junior researchers. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(1):39-46, 2018.

Development of on-line apple bruise detection system

This research aims to develop an on-line apple bruise detection system, using chlorophyll fluorescence images for nondestructive apple bruise detection and analysis. The on-line apple bruise detection system is consisted of a fluorescent image acquisition unit, a fruit carrying revolving tray unit, a conveying unit, and a control unit. The LabVIEW graphical programming language was used to build the control program, and Vision Assistant was used for image processing and analysis. The wavelength of the fluorescence excitation source used was 460 nm. A color camera captured the fluorescence released from Golden Delicious apple, and the wavelength was 680 ± 10 nm. The fruit was revolved by the fruit carrying revolving tray, 60° each time, revolved six times, so as to shoot the complete apple surface. The image processing procedures of bruise recognition include image preprocessing, medium filtering, regional binarization, background removal, noise filtering and hole filling for recognition, and analysis of bruise blocks. This study applied 67.9 ± 4.84N, 82.1 ± 4.57N and 102 ± 8.44N impact forces to apples respectively to make bruises. The test results showed that the proposed on-line apple bruise detection system could recognize the apple bruise 100% after 45 min from the impact on apples. The prototype system could inspect 92 apples for bruise automatically hourly on an average. This study has successfully built an on-line apple bruise detection system, and the inspection of the system may be accelerated in the future for commercial uses.

A new method for aerodynamic test of high altitude propellers

A ground test system is designed for aerodynamic performance tests of high altitude propellers. The system is consisted of stable power supply, servo motors, two-component balance constructed by tension-compression sensors, ultrasonic anemometer, data acquisition module. It is loaded on a truck to simulate propellers’ wind-tunnel test for different wind velocities at low density circumstance. The graphical programming language LABVIEW for developing virtual instrument is used to realize the test system control and data acquisition. Aerodynamic performance test of a propeller with 6.8m diameter was completed by using this system. The results verify the feasibility of the ground test method.

Parametric System Identification using Closed loop Step Response

Objectives: Present work describes the development of a dynamic model of laboratory scale level process using System Identification toolkit from LabVIEW graphical programming language. Methods/Statistical analysis: The dynamic characteristics of industrial processes are affected when they are recognized with different operating conditions. It is always advantageous to have an efficient model to design and implement suitable control configuration to obtain better performance. The identification process has several stages. Findings: The first stage comprises design of experiment, conduction, collection of experimental data. Useful portion of the input output data is selected and preprocessed to eliminate any outliers. In the second stage the experimental data is prepared in to different datasets which are further used to estimate autoregressive exogenous (ARX) models. Application/Improvements: Estimated models are simulated in both direct and indirect methods and the results are compared to draw conclusions.

Single-tone and Polyharmonic Eddy Current Metal Detection and Non-Destructive Testing Education Software

This paper describes the design of a measuring chain for polyharmonic metal detectors used for education in laboratory exercises at Czech Technical University in Prague, Faculty of Electrical Engineering, Department of Measurement. The Measuring chain is composed of DDS signal generator, Digitiser and PC with software programmed in Labview. Eddy current principles or more specifically eddy current metal detectors are an important part of nondestructive testing, instrumentations and measurement. A short introduction to the background and principles of eddy current metal detectors are presented. Next part of the article deals with a brief description of the most common methods, as well as, non-traditional polyharmonic methods for eddy current metal detection. The following part contains an implementation of the proposed algorithms in LabVIEW graphical programming language. Finally, the created program for education of eddy current metal detectors and results obtained on the metal detector ATMID are discussed.

LabView-based Modeling and Evaluation of Solar Photovoltaic Cells Energetic Efficiency

As it is well known, an accurate knowledge of solar photovoltaic (PV) cell parameters from experimental data is of major importance for estimate their performances and to implement high energetic efficiency PV plants. In the last decade several solar cell models, respectively a high amount of software toolkits have been developed to evaluate their electrical behavior and performances. This paper is focused to introduce a LabView graphical programming language based solution to conveniently modeling, simulate, and evaluate solar PV cells energetic efficiency. By using their well known electrical equivalent circuits a fast and accurate PV simulator has been designed and implemented for research and energetic efficiency studies. The simulation models used has been validated through comparison of the obtained characteristics with the ones given by the manufacturers of PV panels. The computer-aided simulation results carried out are in a good agreement with the manufacturer’s catalogue data and the LabView-based program can serve as a very useful toolkit for engineers or researchers who require an accurate PV simulator and evaluate the performances of any photovoltaic module.

Design and implementation of RELab system to study the solar and wind energy

Abstract It is well known that renewable energy, today more than ever, has undergone an exponential development. Thus, it is necessary to create an efficient, compact and relatively cheap system to be used in education and research, which allows studying these types of energy. The concept, design and implementation of such a system – RELab are presented in this paper. The RELab system is a very useful tool for students and engineers to learn about the two types of renewable energy: solar and wind energy. The system has two components: the NI ELVIS platform and the RELab add-on. The RELab add-on is a modular one and it can be easily redesigned for using the photovoltaic cell, the wind turbine and the solar thermal collector. The software used is built in the graphical programming language LabVIEW, and it is flexible and open.

Online monitoring and accident diagnosis aid system for the Nur Nuclear Research Reactor

This paper deals with the design of a computerized monitoring and diagnosis aid system (CMDAS) for the Nur Nuclear Research Reactor based on real-time plant-specific safety parameters. The CMDAS carries out early detection and identification of accidents that might affect this reactor using supervised neural networks. The graphical programming language LabVIEW is used for creating a human--operator interface, networking, embedding the diagnosis procedure, and handling and storing the data. The methodology presented in this paper can be adapted for any nuclear research reactor.

Método para calcular la eficiencia cuántica y la respuesta espectral de celdas solares usando LabVIEW

&lt;p&gt;En este trabajo se presentan los procedimientos clásicos para calcular la densidad de corriente espectral de cortocircuito para la base y para el emisor de una celda solar. Posteriormente, se calculan la eficiencia cuántica y la respuesta espectral. El método es realizado a partir de instrumentación virtual mediante el lenguaje de programación gráfica LabVIEW.&lt;/p&gt;&lt;p&gt;Este programa procesa los datos de longitud de onda, el coeficiente de absorción, el espectro de radiación y el coeficiente de reflexión para desarrollar el análisis mencionado y permite exportar a archivos en formato .xls, la información obtenida. Los resultados indican para una celda solar de silicio; una densidad de corriente espectral de cortocircuito del emisor de 24,3 mA/cm2μ (valor máximo) y de 61,6 mA/cm2μ (valor máximo) para la base. La eficiencia cuántica interna alcanzó el 97% para los 0,65 μm; mientras que la respuesta espectral interna registró 610 mA/W en los 1,45 μm.&lt;/p&gt;

Note: Design and development of wireless controlled aerosol sampling network for large scale aerosol dispersion experiments.

Wireless based custom built aerosol sampling network is designed, developed, and implemented for environmental aerosol sampling. These aerosol sampling systems are used in field measurement campaign, in which sodium aerosol dispersion experiments have been conducted as a part of environmental impact studies related to sodium cooled fast reactor. The sampling network contains 40 aerosol sampling units and each contains custom built sampling head and the wireless control networking designed with Programmable System on Chip (PSoC™) and Xbee Pro RF modules. The base station control is designed using graphical programming language LabView. The sampling network is programmed to operate in a preset time and the running status of the samplers in the network is visualized from the base station. The system is developed in such a way that it can be used for any other environment sampling system deployed in wide area and uneven terrain where manual operation is difficult due to the requirement of simultaneous operation and status logging.

Design and Implementation of a Wireless Networked Water Level Control System

The design of a wireless water level control system is introduced and discussed in detail. In this system, the wireless Proportional Integral (PI) controller is developed using the LabVIEW graphical user programming language. Zigbee wireless technology is chosen for the wireless data transfer system. The experimental testbed was built and the system software and hardware were implemented. In order to compare the performance of the wired and wireless system, a corresponding wired water level control system was built. Experimental results show that under the same PI parameters, the settling time of the wired system is 3.3 times faster than the wireless system. However, the percent overshoot using the wireless controller is 4% smaller.