Automated Data Acquisition System Research Articles

Desempenho operacional de conjunto trator-recolhedora de feijão

Estudos sobre a otimização do processo de colheita de grãos, dentre os quais, os de feijão, têm sido realizados pelo desenvolvimento e aperfeiçoamento de máquinas agrícolas, com a finalidade de aumentar o desempenho operacional, tornando-as mais eficientes e seguras, bem como aumentar a qualidade dos grãos colhidos. A avaliação do desempenho operacional de uma máquina viabiliza o seu emprego de forma técnica e economicamente organizada. Diante disso, este trabalho foi desenvolvido com o objetivo de avaliar o desempenho operacional de um conjunto trator-recolhedora de feijão. Foi utilizado um sistema de aquisição automática de dados, o que permitiu a coleta de dados, em tempo real, incluindo torque requerido e rotação da tomada de potência (TDP), e velocidade de deslocamento da recolhedora de feijão. Foram determinadas, também, a capacidade de processamento da máquina e as perdas ocorridas na área. O maior valor de torque requerido na TDP observado, durante ensaios de campo para a rotação de 7 Hz na TDP, foi de 731 Nm, enquanto, para a condição de 9 Hz, foi de 907 Nm. O conjunto apresentou, durante os ensaios de campo, capacidade média de processamento de 0,85 kg s-1, para área com produtividade média de 0,22 kg m-2. O produto foi colhido com umidade média de 13,6% b.u. em área de plantio direto e, nessas condições, o valor de perda encontrado totalizou 11,15%.

Sistema de aquisição automatica de dados para o gerenciamento de operações mecanizadas

Para difundir e popularizar técnicas de gestão de informações na agricultura são necessários esforços para prover o usuário de ferramentas de análise e de avaliação operacional. A versatilidade do trator agrícola o torna uma enorme fonte de informações que, se bem obtidas, analisadas e interpretadas, podem subsidiar o gerenciamento operacional da propriedade agrícola. Este trabalho apresenta o desenvolvimento de um sistema de aquisição automática de dados projetados para o levantamento de informações de campo. O sistema foi concebido para determinar a posição do veículo através de sistema de posicionamento global (GPS), juntamente com o consumo de combustível, a rotação do motor e a velocidade de deslocamento. Foram realizados experimentos visando verificar o funcionamento do sistema, por meio de da confrontação com outras técnicas de determinação do consumo de combustível, da rotação do motor e da velocidade de deslocamento. Concluiu-se que o consumo de combustível, não exige correção de dados, e a determinação da rotação do motor requer calibração.

Automatic Data Acquisition System for Offshore Oil Pipeline Magnetic Flux Leakage On-line Inspection

In order to assure the safety of oil pipeline transmission, it is very important to continue routine inspection of offshore pipelines to identify defects or corrosions as early as possible. A high-speed inspection data acquisition system was developed for the magnetic flux leakage (MFL) method, with 12 bit sampling precision and 1.25 M/s sampling frequency. This system consists of a micro-computer, electronic memory, pre-processing circuit, power unit, digital signal processor (DSP), Field Programmable Gate Array (FPGA) and other components. The method adopts hardware and software cooperation to control data acquisition, filtering, encoding, handling, storage and transmission. The main function is MFL signal pre-processing, real-time data acquisition, de-noising and data compression. The basic characteristics of the system, design considerations, data filtering, data compression methods and experiment results are described. Experiments showed the system has a good performance.

A Sophomore Capstone Course in Measurement and Automated Data Acquisition

A novel multidisciplinary course (Engineering Applications III) was developed that integrates knowledge gained and tools acquired from the introductory freshman circuits, mechanics, and C/C++ courses. It is built around the concepts associated with automated data acquisition systems. This three-quarter-hour, laboratory-intensive course uses a suite of data acquisition equipment located in the computer aided teaching laboratory at the University of Denver, Denver, CO. The presentation format is two lectures and one three-hour laboratory per week. The lectures are designed to cover material that directly supports the laboratories. Early in the course, laboratories explore the subsystems of an automated data acquisition system. The students then learn the operation of a PCMCIA (personal computer memory card international association) data acquisition card, write C/C++ programs to control the data acquisition, learn the operation of analog-to-digital and digital-to-analog converters, and learn the use of the C/C++ commands provided for controlling these subsystems. These concepts are introduced while doing typical experiments dealing with the measurement of temperature and strain and the evaluation of a temperature controller.

A Small-Volume Apparatus for the Measurement of Phase Equilibria.

An apparatus has been designed and constructed for the measurement of vapor-liquid equilibrium properties. The main components of the apparatus consist of an equilibrium cell and a vapor circulation pump. The cell and all of the system valves are housed inside a temperature controlled, insulated aluminum block. The temperature range of the apparatus is 260 K to 380 K to pressures of 6 MPa. The uncertainty of the temperature measurement is 0.03 K, and the uncertainty in the pressure measurement is 9.8 × 10−4 MPa. An automated data acquisition system is used to measure temperature and pressure at equilibrium. The apparatus has been performance tested by measuring the vapor pressures of propane, butane, and a standard mixture of propane + butane.

An automatic data acquisition system for on-line training of artificial neural network-based air handling unit modeling

Air-conditioning systems are highly non-linear. A conventional air-conditioning control cannot achieve thermal comfort environments all the times. Artificial neural networks have been proven to be successfully applicable in this area. However, they required on-line field data to re-tune themselves. In this paper, a fully automatic data acquisition system was developed for this purpose. The system consisted of a real air-handling unit, thermal sensors, data acquisition boards and a computer with an acquisition program. Substantial experiments were carried out to capture the operating characteristics of the real air-conditioning plant. With the help of the acquisition system, a neural network-based model was built which could accurately predict the behaviors of the plant. A practical optimal control is thus possible. The methodology in this paper, the proposed acquisition system with the neural network under on-line training, can be applied in other areas for better control performances.

A DIGITAL EVENT RECORDER FOR MAPPING FIELD OPERATIONS

When site-specific field operations depend on real time decision making, additional equipment is often requiredto document the work. To fulfill this need for one class of field operations, an automated data acquisition system was developedto document real time single-value treatments. Off-the-shelf components were used to minimize system development timerequirements. The rugged system was based on a single board computer and included solid-state data storage. Laboratorytests were conducted to evaluate system performance. In the laboratory, the system documented a pre-defined series of digitalpulses, and measured integrated duty cycle was compared with actual integrated duty cycle. Maximum error (dimensionless)was 0.0026. A field verification exercise was conducted to confirm system performance under typical field conditions. Thesystem was used to document the activity of a selective sprayer operated over a known foliage pattern. Map layers of foliagelocation and sprayer actuation were in agreement. Systems have been successfully deployed by several researchers studyingherbicide application using selective sprayers. Other possibilities for use include documenting manual spot spraying for lateseason weeds, selective sub-soiling in high traffic areas, and targeted replanting after inconsistent seedling emergence.

Diurnal Variations of Snow Precipitation in Wakasa Bay during Winter

The diurnal variation of snow precipitation in the west coastal area near Wakasa Bay has been investigated for two winter seasons of 2001 and 2003 using surface precipitation radar, rain gauge, and satellite infrared data. Radar reflectivity-derived precipitation intensity shows a clear diurnal cycle within Wakasa Bay for both years, although the cycle is clearer in 2001 than in 2003. The precipitation maximum occurs in the early morning, and the minimum occurs in the evening. Using radar data collected during January 2003, the precipitation diurnal cycle within the Bay is compared with three nearby regions: offshore—open water region to the north, inland—land region to the northeast, and inshore—coastal region to the northeast. It appears that all the other three regions have the precipitation maximum during the day and the minimum during night, although the diurnal variation inland (over land) is very small. Additionally, in the offshore region, there exist two precipitation maxima and minima during a 24-hour day. Analysis of precipitation data from AMeDAS (Automatic Meteorological Data Acquisition System) rain gauge stations basically agrees with the radar observations. It shows that a similar diurnal cycle, found in the radar data within Wakasa Bay, can also be found for coastal stations, although the different patterns are shown depending on the location and time period in 2003. When averaging data from both January and February during 2001 and 2003, the diurnal cycle tends to be smoothed out. Cloud top temperature and cloud fraction derived from satellite infrared data do not show a clear diurnal cycle within Wakasa Bay, nearby inshore and inland regions, although the decreases of brightness temperatures are seen around noon in the offshore region for both cases of 2001 and 2003. Analysis using collocated satellite and radar data indicates that cloud top temperature has little skill in reflecting surface precipitation for the winter convective clouds associated with cold air outbreaks. Finally, possible causes of the diurnal variation are discussed, including local land-sea breeze and mountain wind effects, as well as the radiative cooling effect.

ESTIMATION OF GRAPEVINE CROP MASS AND YIELD VIA AUTOMATED MEASUREMENTS OF TRELLIS TENSION

A novel approach was devised to estimate vegetative growth and fruit mass (i.e., yield) in grapevines by continuouslymeasuring the tension in the horizontal (cordon) support wire of the trellis. Load cells installed in-line with the cordon wire wereconnected to an automated data acquisition system, a major departure from the viticulture industrys standard method of collectingfruit samples by hand two or three times per growing season. Each experimental row in the vineyard was calibrated to determinethe change in tension in that row in response to an increase in known mass on the cordon wire. The effects of temperatureon wire tension were removed by post-processing with a regression-based empirical protocol, which corrected the raw datato a standard temperature. Because data were averaged over 15 min, wind gusts appeared to have little measurable effect onthe tension measurement. A smoothing algorithm removed remaining transient disturbances in the data without masking significantevents like crop thinning or harvest. Results to date suggest a linear relationship between wire tension and fruit mass thatvaries among rows, but not within a row, during a single season. Yields were between 4.5 and 20.2 t ha-1 (2 to 9 t acre-1).

The effects of pH and dissolved organic carbon on the toxicity of cadmium and copper to a freshwater bivalve: further support for the extended free ion activity model.

The extended free ion activity model (FIAM) was developed by integrating concepts from the original FIAM into biological receptor theory, to obtain a conceptual model that more precisely quantifies the interaction of chemical species at biological receptor sites. The extended FIAM was tested by determining the acute (48 h) valve movement behavior (VMB) (measured in terms of the duration of valve opening) of the Australian freshwater bivalve, Hyridella depressa, to increasing concentrations of total Cd or Cu, in a standard synthetic water under conditions of varying pH (6.5-7.5) and/or dissolved organic carbon (as model fulvic acid (FA)) concentrations (0-11.2 mg L(-1)). Valve movement behavior, measured using an automated data acquisition system, was shown to be a quantifiable and rapid, real-time endpoint for assessing the toxic effects of Cd and Cu exposures. The VMB of H. depressa to Cd was independent (p > 0.05) of pH and/or model FA concentration. In contrast, the VMB of H. depressa to Cu was highly dependent (p < 0.001) on pH and/or model FA concentration; individuals were more sensitive to Cu at low pH and model FA concentrations. The VMB of H. depressa was directly proportional to the activity of the free metal ion (Cd2+), for the linear region of the concentration-response curves. In contrast, the VMB of H. depressa was a weighted function of the activities of the free metal ion and the 1:1 metal hydroxide species (i.e. 2.02 x Cu2+ + CuOH+), whereby Cu2+ had a two-fold greater binding affinity than CuOH+ at the cell membrane surface. Moreover, the results for Cd and Cu are consistent with the extended FIAM, as opposed to the original FIAM, where the result for Cu would be regarded as an exception. The extended FIAM explained 98% of the variability in VMB, whereas the original FIAM explained only 63% (i.e. an improvement of 35%). The improved predictability of organism response to Cu is relevant to advancing water quality guidelines for protecting aquatic biota.

Programa computacional para aquisição de dados para avaliação de máquinas agrícolas

A aquisição de dados é um dos principais problemas enfrentados por engenheiros e pesquisadores responsáveis pela realização de testes de máquinas agrícolas, devido à alta complexidade dessas máquinas. Para estabelecer os parâmetros relacionados ao seu desempenho, uma série de variáveis precisam ser monitoradas. Diante disso, o objetivo deste trabalho foi desenvolver um programa de computador para aquisição automática de dados a serem utilizados na avaliação de máquinas agrícolas. O sistema foi implementado utilizando-se o programa de computador LabVIEW versão 6i e equipamentos da "National Instruments". Desenvolveram-se Instrumentos Virtuais (VI) para os seguintes tipos de sensores: célula de carga, torquímetro, sensor de rotação tipo sensor indutivo e sensor de velocidade tipo radar. No trabalho realizado implementou-se um sistema de aquisição automática de dados e se desenvolveu o aplicativo AvaliaMA para avaliação de máquinas agrícolas, o qual foi desenvolvido buscando-se a coleta de dados de forma eficiente e se eliminando os erros tradicionais gerados pela coleta de dados convencional, como anotações incorretas em planilhas e perda de dados. Observou-se, durante os ensaios, facilidade de operação do sistema, permitindo rapidez na operação de aquisição de dados, e a capacidade de se combinar o sistema implementado para atender a demandas de diversas pesquisas, podendo ser utilizado em diferentes tipos de máquinas agrícolas.

The IMGC-CNR flowmeter for automatic measurements of low-range gas flows

The IMGC-CNR constant pressure and variable volume gas flowmeter is described together with its automatic electronic control and data acquisition system. It is used to produce low pure-gas throughputs in the 10 −3–10 −8 Pa m 3 s −1 range, at the reference temperature of 294.15 K. This flowmeter may be used for both the pressure generation in the continuous-expansion system and for leak calibrations with reference to vacuum. Uncertainty evaluation is also discussed in the whole range of use, including the repeatability of the flowmeter itself: at present, the relative combined standard uncertainty ranges from a minimum value of 0.2% to a maximum of 0.8%.

Characterization of a pneumatic differential pressure transfer standard

The paper describes a novel method for the characterization of a pneumatic differential transfer standard in the differential pressure range 0 Pa to 3.5 MPa up to a high line gas pressure of 7.0 MPa. In view of the advances in the field of automated data acquisition systems an effort has been made to incorporate such a system in the conventional pressure measurement, which uses relatively high accuracy piston gauges and the user-friendly digital transducer. The transfer standard used in the present work is a silicon strain gauge transducer, model PMP 4115, made by Druck, with an output voltage range of 0 V to 5 V with a readout unit/power supply DPI 282. The transducer was characterized against the secondary standard, which is a twin pressure balance, Model 5502, made by Desgranges et Huot, France, designated as NPL-8. The characterization was done through an automated data acquisition system using a model 9118HR A/D interface card made by Adlink, as well as the readout unit DPI 282. The uncertainty estimations showed up considerable differences between the two modes of data acquisition. The observed results were further used to generate a regression equation for the estimation of differential pressure at any given line pressure.

Portable pilot plant for evaluating marine biofouling growth and control in heat exchangers-condensers

Biofouling frequently involves a serious impediment to achieving optimum operating conditions in heat exchangers-condensers. The economic coat and energy losses associated with this phenomenon are significant and the environmental impact of biocides must satisfy stringent regulations. A portable pilot plant has been designed in order to carry out in-situ experimental study as biofilm is formed under thermal and hydrodynamically controlled conditions. The pilot plant has an automatic monitoring, control and data acquisition system, which automatically processes data from indirect measure of fouling in terms of increased fluid frictional and heat transfer resistances. A particular method is used and proposed for direct measuring and biofilm characterization. Once we know the actual film thickness, we can calculate the effective thermal conductivity of the layer by using the appropriate heat transfer equations.

Development of automated real-time data acquisition system for robotic weld quality monitoring

The lack of reliable non-contact, non-destructive, online sensors with the ability to detect defects as they form and with the capacity to operate at high temperatures and in harsh environments is a big obstacle to fully automated robotic welding. This paper presents a non-contact automated data acquisition system for monitoring a robotic gas–metal arc welding process based on laser ultrasonic technology. While a robot welds between two 1040 steel strips, a Nd:YAG Q-switched pulse laser generates ultrasound on one side of the weld by ablation, and a non-contact electro-magnetic acoustic transducer (EMAT) placed on the opposite side of the weld detects ultrasound transmitted through the weld bead. Ablation is employed because high temperature specimens require strong signals to compensate for attenuation within the bulk of the material. The data is then analyzed to determine the time required for ultrasound to travel from the laser source to the EMAT, termed as the time of flight (ToF). When experimental ToF is compared to theoretical ToF, it is determined that surface waves are detected by this system. Therefore, this system can measure weld bead reinforcement distance. In most cases, weld bead geometry is an indication of the weld quality, and can be used as feedback to control a welding process.

The Las Campanas Infrared Survey Camera

The Las Campanas Infrared Survey Camera is a near-infrared (1.0–2.5 μm), wide-area instrument used to detect and measure the photometric properties of galaxies out to large redshifts, z > 2. The camera, a modified Offner 1 : 1 reimaging optical system, is mounted at the f/7.5 focus of the 2.5 m du Pont Telescope. The detectors are four Rockwell 1024 × 1024 HgCdTe (HAWAII) arrays operating at a scale of 020 pixel-1. With four telescope pointings, the instrument produces a pipelined mosaic of J, H, or Ks images 13' × 13' on the sky, with a measured point-spread function as good as 038 FWHM. The good imaging quality results in part from fast tip-tilt guiding on stars within a 9' × 9' field centered on the optical axis of the telescope. Appropriately bright guide stars are found within 2 s from a catalog of 5 × 107 stars and presented as a finding chart to the observer. The optical, mechanical, and thermal design choices and their associated engineering implementations are discussed in some detail. The detector readout electronics, the automatic data acquisition and control system, and our data reduction pipeline are also described. The design goals of the camera—excellent imaging quality and throughput, low flexure and internal background, and 5 Hz on-axis guiding, are all realized and quantified.

Production and test of monitored drift tubes for the muon spectrometer of the ATLAS experiment

ATLAS is one of the two general-purpose experiments being built for the Large Hadron Collider at CERN. Its muon spectrometer consists of very high-precision chambers made of drift tubes. Up to now, more than 5000 monitored drift tubes (MDTs) have been constructed and tested at the University of Calabria, Italy, for ATLAS barrel system chambers of the muon detector. This paper reports the critical MDT assembly techniques in detail, including the automatic electronics system and data acquisition system. The extensive tests performed on individual drift tubes and the first results and experience are also reported.

15.1: A Method to Measure the Optical Uniformity of LCOS Displays

AbstractA novel method to measure the optical uniformity of LCOS displays has been developed. The technique measures spatial variation in the electro‐optic curve over the active area of a display using a CCD and automated data acquisition system. Spatial non‐uniformities in cell gap of 1/10th a fringe are measured and characterized quickly (&lt;15s). The experimental method will be described and the results of measurements and data analysis on sample LCOS imagers will be presented. The method is well suited to monitoring process capability and has been implemented as an in line test.

Automation of the particle dosimetry and the dose application for radiobiological experiments at a vertical proton beam

A facility with a vertical beam for radiobiological experiments with low-energy protons has been setup at the Tandem accelerator at Erlangen. This energy region is optimal to investigate the biological effects of the linear energy transfer in the Bragg region under physiological conditions. A new automated data acquisition system for dosimetry and monitoring based on a personal computer was developed and optimized for this setup. A specially designed sample holder offers possibilities of cooling or changing of atmosphere during irradiation. First irradiations of biological samples have shown the functionality of the setup.

PROTOCOL FOR EARLY DETECTION AND EVALUATION OF INHIBITORY WASTEWATER USING COMBINED AEROBIC RESPIROMETRIC AND ANAEROBIC BATCH TECHNIQUES

Faced with the task of treating significant volumes of complex industrial wastewaters, the biological components of municipal wastewater treatment plants are operating under the risk of toxic or inhibitory contaminants from the industrial effluents that may be detrimental to their operation. This might lead to undesirable effluent toxicity and/or result in permit violations. Therefore, there is a need for upset early warning systems that can protect full-scale plants from toxic or inhibitory constituents in the incoming wastewaters. This study focused on the development of a protocol for rapid detection of potentially toxic inhibitory or toxic wastewaters using combined aerobic respirometric and anaerobic batch techniques. Aerobic respirometers equipped with automated data acquisition systems were used as potential early warning devices. The inhibition effect on carbon and nitrogen oxidation was assessed. The degree of inhibition was evaluated as the concentration causing 50% reduction in microbial activity, which was estimated by an inhibition model. Anaerobic toxicity assays were also conducted to evaluate the inhibitory effects of the toxic compounds to anaerobic inocula obtained from a master culture reactor fed with ethanol. The developed protocol for early detection of toxicity was validated using wastewater samples from a biotechnology industry and a food processing industry, and pure chemicals such as furfural and phenol. Varying degrees of sensitivity were observed in the study when different groups of microorganisms, wastewater samples, and chemicals were tested. The comparison of aerobic and anaerobic inhibition suggested the importance of using both aerobic and anaerobic cultures to maximize the necessary sensitivity of the protocol.