Multichannel Data Acquisition System Research Articles

A prediction-error-based method for data transmission and damage detection in wireless sensor networks for structural health monitoring

In this work, a prediction-error-based method that aims to reduce the amount of data transmission and storage in structural health monitoring wireless sensor networks (WSN) while keeping the damage detection capabilities intact is presented. WSNs offer tremendous promise for accurate and continuous structural monitoring using a dense array of inexpensive sensors and possess many advantages over conventional wired systems, particularly for large civil infrastructures. This paper validates the studied approach with the data collected during a test on a three-story steel frame mounted at the ELSA laboratory of the EU Joint Research Center in Ispra, Italy. The frame is tested with and without steel bracing, which results in non-sway behavior and sway frame responses. The excitation is provided by a shaker mounted on top of the frame. Accelerometer signals are collected by a multi-channel data acquisition system. The proposed method has been tested extensively via recorded experimental data and it offers considerable saving in transmitted energy while at the same time keeping the ability to detect changes or damage in the structure.

Development of Multichannel Data Acquisition System Based on Wheel Load Measuring Plate

The wheel load measuring plate is a force sensor based on strain measurement, it can bear simultaneously multidimensional force load and identify radial wheel load by decoupling. The measuring plate can output multichannel voltage signal, usually each channel has the properties of weak signal, strong noise, poor anti-jamming ability. The paper discusses the development of a multichannel data acquisition system for the wheel load measuring plate and conducts the experimental verification, through the data acquisition system achieve time-sharing acquisition of multichannel data, improving the precision and anti-jamming ability of wheel load measurement system.

Vehicle-Carrying Multi Channel Data Acquisition System Based on the CompactRIO

In order to obtain the key parameters which required by the Vehicle-Carrying test, the multi-channel data acquisition system based on CompactRIO embedded platform was developed. This system was satisfied the requirement of high reliability, inexpensive, portable and rapid configuration, Then, synchronized control technology such as queue, FIFO, interrupt and the superior system architecture which is compare to the state machine has been introduced in detail. Finally, availability and stability of the system were proved through the pressure text of data acquisition.

Multi-Channel Data Acquisition and CAN Communication System Based on Single-Chip Microcomputer

Aimed at the problem that the traditional data acquisition system design with low efficiency and high cost. It is proposed that the C8051F040 microcontroller is based on the integrated A/D converter and CAN controller; utilize dynamic control simulation input quantity into the built-in A/D converter, process and store the data through the micro-processing unit, and use integrated CAN controller to transmit the data. From schematics design to the boards development, we have achieved the functions that acquisition of multi-channel data combined with CAN network communication through hardware and software debugging. The design of this product is small, powerful and wide used. It has good application and development prospects.

The Design of 12-Channels Acquisition and Storage System Based on FPGA and AD7492

This paper introduces the principle and realization process of multi-channel data acquisition and storage system based on FPGA, A/D converter, FLASH and USB microcontroller. The system’s controlling core is FPGA. FPGA finished the switch of the multi-channel analog switch、A/D conversion、data compilation and storaging in the FLASH and uploading the data to PC by USB microcontroller. Test result can indicate that the system is simply and practical .The system can finish the real-time acquisition and processing for 12 input signals, sampling rate up to 1MSPS.

Multi-Channel Peripheral Data Acquisition System based on Labview and SCM

Multi-Channel Peripheral Data Acquisition System based on Labview and SCM

A New Design of Signal Source for Crosstalk Test of Multi-Channel Data Acquisition System

For the multi-channel data acquisition system, crosstalk significantly affects the sample accuracy. Through analyzing the mode of multiplexer and the sampling timing sequence, we demonstrated that crosstalk effect mainly results from the switch of multiplexer for the low- frequency multi-channel data acquisition system. A new crosstalk testing method based on phase-shift rectangular waveform for the multi-channel data acquisition system was proposed. The phase-shift rectangular waveform was designed. Experiments were conducted to test crosstalk effect of the multi-channel data acquisition system. The experimental results were demonstrated that the proposed approach based on the phase-shift rectangular waveform exhibits a distinct feature in effective channel crosstalk testing, compared with waveforms of other types. Thus, the proposed method is effective to detect crosstalk of the multi-channel data acquisition system.

Design and Implement of Data Acquisition System Based on Reconfigurable Computing

Data acquisition begins with the physical phenomenon or physical property to be measured. Examples of this include temperature, gas pressure, and light intensity, and force, fluid flow, regardless of the type of physical property to be measured. Physical property converted into digital, and then by the computer for storage, processing, display or printing process, the corresponding system is called data acquisition system. With the rapid development of computer technology, data acquisition systems quickly gained popularity. A variety of products based on digital technology have been created. Digital System spread quickly; it’s mainly the following two advantages: the first is the digital processing flexible and convenient; the second is a digital system is very reliable. The main idea of Reconfigurable computing technology [1] is using the FPGA [2][3] allows the system has a dynamically configurable capacity, suitable for harsh environment applications, improve the speed of data processing. By the use of dynamic reconfigurable FPGA devices can be realized on the hardware logic function modification, application of reconfigurable computing technology can improve the speed of data processing. Data acquisition system is widely applied in many fields, and often used the abominable working environment place. The reconfigurable computing technology, can greatly improve the data acquisition system reliability and safety. The paper introduces a kind of multi-channel data acquisition system based on USB bus and FPGA, the factors affecting the performance of system are discussed, and describes how to use reconfigurable computing technology to improve the efficiency of data acquisition system while reduce energy consumption. The system in this paper uses AD's AD9220, ALTERA's EP1C6-8 and IDT's IDT70V24, Cypress’s CY7C68013.

Design of SPI Bus Communication in the Multi-Channel Data Acquisition Systems

the system structure of a multi-channel data acquirement system is introduced in this paper. The communication interaction circuit between the main control system and signal conditioning circuit is described. The SPI bus communication type is adopted between C8051F320 and FPGA. The speed and accuracy of datum transfer must be considered in the communication design, so the CRC calibration is used.

The Design of Embedded Multi-Channel Data Acquisition System

This paper analyzes the Flash Memory interface, SDRAM interface, Ethernet interface and Serial-port expansion circuit. The Embedded Multi-channel Data Acquisition System is designed by MCF5272 microprocessor. The main control system of MCF5272 includes SDRAM, Flash and BDM interface and so on. At the software design, we main introduce the compile and develop of bootload and the compiler and debugging environment of μClinux build. On this base, the general methods and points of the embedded system hardware design were summarized.

TH‐A‐213CD‐09: The Use of Scintillating Fibers for Proton Imaging Purposes

Purpose: To determine the feasibility of using scintillating fibers for proton imaging purposes.Methods and Materials: This study considered 2mm × 2mm square BCF‐20 bicron fibers from Saint‐Gobains CrystalsTM which emit a green spectrum with a peak at 492nm, and present a 2.7ns decay time, therefore making them suitable for particle‐by‐particle analysis. Photomultiplier Tubes (PMT) with approximately 3ns response pulses and 2×2.5mm sensitive areas were coupled to the fibers. Particle interactions were acquired with a fast oscilloscope (1.5GHz, 20Gs/s) for single event analysis, as well as with a multichannel data acquisition system for stream of events using multiple fibers simultaneously. A mono‐chromatic proton beam set to different energies was used to irradiate individual fibers and the light output spectrum was recorded. Two individual fibers, one with and one without optical grease at the fiber‐PMT interface, were also used for measurements in order to assess the benefit from using optical grease. Results: Individual pulses were first recorded to assess the quality of the system. This highlighted the non‐relevance of using optical grease versus a direct fiber‐PMT interface. Light spectra were subsequently acquired with different incident proton energies. These correspond to the light output from each fiber, hence the energy deposited (dE/dx) by single protons inside the scintillator. The obtained data is in good agreement with the ICRU data which shows that scintillating fibers can be used to record incident energy from protons on a particle‐by‐particle basis. Conclusions: Preliminary results show that scintillating fibers could be used for proton imaging. A prototype made of 64 scintillating fibers (2 perpendicular arrays of 32 channels) is currently under conception at MGH, and avant‐garde pictures will soon be acquired with this first‐of‐a‐kind proton radiography system.

Real‐time scintillation array dosimetry for radiotherapy: The advantages of photomultiplier detectors

In this paper, a photomultiplier tube (PMT) array dosimetry system has been developed and tested for the real-time readout of multiple scintillation signals from fiber optic dosimeters. It provides array dosimetry with the advantages in sensitivity provided by a PMT, but without the need for a separate PMT for each detector element. The PMT array system consisted of a multianode PMT, a multichannel data acquisition system, housing and optic fiber connections suitable for clinical use. The reproducibility, channel uniformity, channel crosstalk, acquisition speed, and sensitivity of the PMT array were quantified using a constant light source. Its performance was compared to other readout systems used in scintillation dosimetry. An in vivo HDR brachytherapy treatment was used as an example of a clinical application of the dosimetry system to the measurement of dose at multiple sites in the rectum. The PMT array system was also tested in the pulsed beam of a linear accelerator to test its response speed and its application with two separate methods of Cerenkov background removal. The PMT array dosimetry system was highly reproducible with a measurement uncertainty of 0.13% for a 10 s acquisition period. Optical crosstalk between neighboring channels was accounted for by omitting every second channel. A mathematical procedure was used to account for the crosstalk in next-neighbor channels. The speed and sensitivity of the PMT array system were found be superior to CCD cameras, allowing for measurement of more rapid changes in dose rate. This was further demonstrated by measuring the dose delivered by individual photon pulses of a linear accelerator beam. The PMT array system has advantages over CCD camera-based systems for the readout of scintillation light. It provided a more sensitive, more accurate, and faster response to meet the demands of future developments in treatment delivery.

A Multi-Channel Data Acquisition System and its Performance Analysis Method Based on FPGA

The multiplexer act as the inputs of analog signals, enabling multi-channel analog signal acquisition; then filtered through a certain signal processing to ensure the most effective analog signals into the ADC; after conversion, the digital output is saved in the temporary buffer zone of the FPGA. The whole process is controlled by the FPGA. Finally, apply to the DAC-ADC joint debugging, in compare to the results, 14bit precision is guaranteed.

Multi-channel pre-beamformed data acquisition system for research on advanced ultrasound imaging methods

The lack of open access to the pre-beamformed data of an ultrasound scanner has limited the research of novel imaging methods to a few privileged laboratories. To address this need, we have developed a pre-beamformed data acquisition (DAQ) system that can collect data over 128 array elements in parallel from the Ultrasonix series of research-purpose ultrasound scanners. Our DAQ system comprises three system-level blocks: 1) a connector board that interfaces with the array probe and the scanner through a probe connector port; 2) a main board that triggers DAQ and controls data transfer to a computer; and 3) four receiver boards that are each responsible for acquiring 32 channels of digitized raw data and storing them to the on-board memory. This system can acquire pre-beamformed data with 12-bit resolution when using a 40-MHz sampling rate. It houses a 16 GB RAM buffer that is sufficient to store 128 channels of pre-beamformed data for 8000 to 25 000 transmit firings, depending on imaging depth; corresponding to nearly a 2-s period in typical imaging setups. Following the acquisition, the data can be transferred through a USB 2.0 link to a computer for offline processing and analysis. To evaluate the feasibility of using the DAQ system for advanced imaging research, two proof-of-concept investigations have been conducted on beamforming and plane-wave B-flow imaging. Results show that adaptive beamforming algorithms such as the minimum variance approach can generate sharper images of a wire cross-section whose diameter is equal to the imaging wavelength (150 μm in our example). Also, planewave B-flow imaging can provide more consistent visualization of blood speckle movement given the higher temporal resolution of this imaging approach (2500 fps in our example).

Emission Spectral Tomography With Optical Fiber Bundle

The real time acquisition of the optical radiation information of multi points in free space is a difficult problem for the optical fluid fields testing. Traditional data acquisition systems are based on multichannel charge coupled device (CCD), with which the optical radiation information from multi directions can be obtained. However these systems are hard to fit the requirement of parallel beam imaging, and hence bring great errors of inverse computations. A multichannel real time data acquisition system based on a digital signal processor (DSP) and a number of optical fiber bundles (OFBs) is proposed in this paper for fluid field reconstructions. Each OFB unit can acquire the optical radiation information that transmits into its entrance aperture via a sensor unit consisting of an optical fiber coupler and a phototransistor. The DSP acts as a main controller that switches on the exposure of all phototransistors synchronously based on the mechanism of electronic shutter. The synchronous sensed signals are locked by a peak hold circuit and then outputted to analog-to-digital converters (ADCs), and therefore the real time acquisition of the optical radiation information of multi points in free space can be realized, which offers the original parallel beam imaging data for the fluid field reconstructions.

MULTICHANNEL DATA ACQUISITION SYSTEM FOR VIBROACOUSTIC SIGNALS

The authors have made an attempt to construct a multi-channel data acquisition system for vibroacoustic signals, col­lected for analysis of acoustic field distributions in enclosed rooms and determination of surface acoustic impedance values at the wall surfaces. The scope of the study required a synchronic registration of acoustic pressure by 24 mea­surement microphones, determination of the phase-shift angles between the measured signals and determination of the vibration velocity for the loudspeaker diaphragm. The paper presents the first stage of the research, directly related to the multi-channel system for registration and analysis of vibroacoustic signals. The constructed research tools, due to their modular structure, can be adapted to new tasks, extended by adding new elements (further measurement cards, microphones, accelerometers etc.), what ensures greatflexibility and suitability of the system for realization of advanced acoustical measurements. Open source code and users request for specialized acoustic analyses make the developed software packages a highly prospective research tool both for today and tomorrow.

In vivo three-dimensional photoacoustic imaging based on a clinical matrix array ultrasound probe

We present an integrated photoacoustic and ultrasonic three-dimensional (3-D) volumetric imaging system based on a two-dimensional (2-D) matrix array ultrasound probe. A wavelength-tunable dye laser pumped by a Q-switched Nd:YAG laser serves as the light source and a modified commercial ultrasound imaging system (iU22, Philips Healthcare) with a 2-D array transducer (X7-2, Philips Healthcare) detects both the pulse-echo ultrasound and photoacoustic signals. A multichannel data acquisition system acquires the RF channel data. The imaging system enables rendering of co-registered 3-D ultrasound and photoacoustic images without mechanical scanning. The resolution along the azimuth, elevation, and axial direction are measured to be 0.69, 0.90 and 0.84 mm for photoacoustic imaging. In vivo 3-D photoacoustic mapping of the sentinel lymph node was demonstrated in a rat model using methylene blue dye. These results highlight the clinical potential of 3-D PA imaging for identification of sentinel lymph nodes for cancer staging in humans.

Modal Survey Test and Model Correlation of the CASSIOPE Spacecraft

A comprehensive modal survey test based on multi-input multi-output experimental modal analysis techniques was conducted on the CASSIOPE spacecraft. This paper describes the details of the methodology used to perform the successful experimental modal test to efficiently extract the critical modes of the spacecraft. Results from the modal test have been used to validate the analytical finite element model and to provide confidence in the structural integrity of the spacecraft design. The test was performed on the flight model of the CASSIOPE spacecraft in the final stages of integration, which included all of the payload and bus instruments and electronics boxes. The multiple-input excitation for the spacecraft was generated using two portable electrodynamic modal shakers installed on the top and bottom of the spacecraft to distribute the excitation energy and the response was measured using 81 miniature accelerometers. A digital multi-channel data acquisition system was used to record the time domain data and calculate the frequency domain spectra. Advanced modal analysis software was used to extract modal parameters from the measured data and critical modes were compared with predictions from the finite element model. Most modes identified through the experimental data compared favorably with the predictions. Nevertheless, some differences were large enough to require iterative update of the finite elelement model. The structural dynamics information from the updated finite element model was used to plan the mechanical vibration qualification test and predict the response of the spacecraft to the launch vehicle environmental loads through coupled loads analysis.

Characteristics of Electrode Displacement and Force in Resistance Spot Welding

The behaviors of electrode displacement and force during spot welding were studied. Tests were conducted on a 170KVA MFDC spot welder. Data were collected via a multi-channel high speed data acquisition system, and were analyzed with MATLAB. Behaviors of 5182 aluminium and mild steel in spot welding were compared. Results showed that nugget expansion rate did not reach zero for aluminium as it did for mild steel as nugget grew to a certain size. An electrode force peak was observed and was believed relevant to sufficient nugget size.

A Low-Cost Stand-Alone Multichannel Data Acquisition, Monitoring, and Archival System With On-Chip Signal Preprocessing

The objective of this paper is to design a new generation of affordable sophisticated data acquisition and processing (DAQP) systems. Because of the proposed system hardware reconfigurability, it can be used to meet the need of many real-world applications while keeping the cost of a device low. The hardware implementation of the different processing functions of the device allows for high-speed processing without the need of expensive general-purpose processors, as is the case of computer-based or microcontroller-based data acquisitions (DAQs). The target technology of implementing the proposed design is the system on chip via field-programmable gate array (SoC-FPGA). A four-channel DAQP was designed, developed, and tested in the Embedded Systems Design Laboratory, Tennessee Technological University, Cookeville. Various modules of the conceptual design are implemented and verified. Performance evaluation and cost comparisons are provided. The comparison showed that the results of the proposed instrument are comparable to existing technologies at a fraction of the cost.