High-speed Real-time Data Acquisition Research Articles

The influence of software timing error on measurement accuracy of data acquisition

The application of high-speed real-time data acquisition is becoming increasingly wide spread in industrial field, and its measurement accuracy is also increasing. The closed-loop test system of sine wave signal is constructed by the RIGOL’s DG1022 dual-channel signal source, DS1102C oscilloscope and PCI7489 multifunctional data acquisition card. Three kinds of timing methods, such as Visual Basics (VB) Timer control, multimedia timer function timing and query performance frequency function timing method, were carried out a series of comparative experiments. This paper analyzes the correlation characteristics of the measured voltage peak data, which includes mean value, variance, standard deviation, range, mutation system, deviation, kurtosis and so on, and then finds out the influence rules of software timing error on data acquisition and measurement accuracy. In the high-speed data acquisition, the repeatability error can be reduced from 84.22% to 0.62%, which provides scientific basis and reference for selecting software timing method in different test environment.

Microcontroller based data acquisition system using error reduction technique

The application of high-speed real-time data acquisition is becoming increasingly wide spread in industrial field, and its measurement accuracy is also increasing. In the present study, the development of a USB based data acquisition system is presented here, where a microcontroller based standalone embedded system is used as data collection and also field control device. The data acquisition system has been calibrated in terms of output voltage generated in signal conditioner. The USB device system also calibrated for the error in the output result. Here USB device has been programmed as Human Interface Device (HID) class, hence not requiring any kind of device specific driver. This data acquisition system is utilized to measure the flow of a channel. The flow of water is not acidic.Keywords: USB, microcontroller, PIC, acquisition, data acquisition, programmer, digital

A Real-Time Data Acquisition and Processing Framework Based on FlexRIO FPGA and ITER Fast Plant System Controller

Measurement and control of the plasma in real-time are critical for advanced Tokamak operation. It requires high speed real-time data acquisition and processing. ITER has designed the Fast Plant System Controllers (FPSC) for these purposes. At J-TEXT Tokamak, a real-time data acquisition and processing framework has been designed and implemented using standard ITER FPSC technologies. The main hardware components of this framework are an Industrial Personal Computer (IPC) with a real-time system and FlexRIO devices based on FPGA. With FlexRIO devices, data can be processed by FPGA in real-time before they are passed to the CPU. The software elements are based on a real-time framework which runs under Red Hat Enterprise Linux MRG-R and uses Experimental Physics and Industrial Control System (EPICS) for monitoring and configuring. That makes the framework accord with ITER FPSC standard technology. With this framework, any kind of data acquisition and processing FlexRIO FPGA program can be configured with a FPSC. An application using the framework has been implemented for the polarimeter-interferometer diagnostic system on J-TEXT. The application is able to extract phase-shift information from the intermediate frequency signal produced by the polarimeter-interferometer diagnostic system and calculate plasma density profile in real-time. Different algorithms implementations on the FlexRIO FPGA are compared in the paper.

Development of High-Speed Ultrawideband Ground-Penetrating Radar for Rebar Detection

This paper describes the development of new air-coupled ultrawideband ground-penetrating radar (GPR) for highway pavement and bridge deck inspections that can achieve high spatial resolution and high inspection performance while operating on vehicles driving at regular highway speeds. The major design features include dual-frequency band operation, 8 gigasamples per second high-speed real-time data acquisition, high-speed large volume data transmission and storage, and customized signal-processing algorithms for GPR image enhancement and feature extractions. For design validations, steel reinforcing bar detection experiments in various setups are conducted. The measurement results show good agreement with the subsurface feature configurations.

Design and implementation of high-speed real-time data acquisition system based on FPGA

The electromagnetic radiation will result in information leakage being recovered when computers work. This article presents a high-speed real-time data acquisition system based on peripheral component interconnect (PCI) bus and field programmable gate array (FPGA) for sampling electromagnetic radiation caused by video signal. The hardware design and controlling flow of each module are introduced in detail. The sampling rate can reach 64 Msps and system transfers speed can be up to 128 Mb/s by using time interleaving, which increases the overall sampling speed of a system by operating two data converters in parallel.

Measurement of space-charge distributions in solid insulators underrapidly varying voltage using the high-voltage, high-speed pulsedelectro-acoustic (PEA) apparatus

A new high-voltage, high-speed pulsed electro-acoustic (PEA)apparatus for real-time measurements of space-charge distribution in solidinsulators subjected to rapidly varying voltages is described. Very high-ratePEA measurement is accomplished with the use of a high-speed real-time dataacquisition module known as the `Eclipse' unit and a purpose-builthigh-voltage FET switch pulse generator. Real-time space-charge measurementswith good phase resolving capability can be made under time varying appliedstresses, e.g. voltage transients or ac conditions. The high-field PEA systemhas been used to investigate the space-charge dynamics in polyethylene samplesstressed by 0.2 and 50 Hz sinusoidal ac voltages.

High-speed real-time data acquisition for vector measuring current meters

The authors describe an integrated hardware and software approach used to provide real-time acquisition and display of vector measuring current meter (VMCM) data at high sample rates (0.5 Hz) with supporting data from other instruments of somewhat slower rates. The hardware component consisted of a new circuit board for the VMCM that captured the VMCM data output, stored it, and transmitted it at high speed in response to a request from the data acquisition computer. The data acquisition software ran on a Masscomp 5600 computer under the UNIX operating system. A central control program provided timing information to several software processes that handled serial data acquisition, display, and storage for one or more instruments. Deployed as a part of the Surface Waves Processes Program (SWAPP) experiment, the integrated data acquisition system successfully collected, processed, stored, and displayed data from 19 VMCMs and four other instruments over a 22-day period in February and March of 1990. >