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Vibration analysis is commonly used to assess machinery conditions, earthquake detection, and structural monitoring. Commercially available DAQs (Data Acquisition Systems) feature high costs and limited versatility in terms of end-user hardware/firmware customization, making it difficult to adapt them to the input signal features and add supplementary functionalities. Hence, this research aims to develop a custom acquisition board for detecting vibration signals via IEPE (Integrated Electronic Piezoelectric) sensors, considering the limitations of commercially available systems, and building upon solutions found in the literature. The DAQ board was intended for remote vibration monitoring of infrastructure and machinery for industrial applications, allowing the implementation of predictive maintenance strategies. The proposed DAQ board has two independent and fully configurable channels, which can be set for acquiring signals from IEPE sensors or generic voltage sources. The DAQ board relies on the STM32F401 microcontroller to manage the acquisition from high-speed ADCs, process data, and store them in mass memory (SD card). During acquisition, the DAQ implements a batch acquisition strategy based on a buffer flash memory for temporarily storing ADCs data, which are iteratively poured into mass memory. Also, the board has Bluetooth connectivity to transmit acquired data and receive commands remotely. A prototype of the DAQ board was developed and tested with several waveforms, including vibration signals. The tests showed that the board can acquire vibration signals and compute the FFT onboard. The DAQ demonstrated a good balance between performance, accuracy, flexibility, and cost, making it suitable for several industrial applications and allowing for scalability and integration potential. [ABSTRACT FROM AUTHOR]

The backscatter X-ray system makes an image by detecting scattered particles from an object in the opposite direction by Compton scattering. This system has the advantage of detecting drugs or explosives composed of organic substances. In this study, we developed a backscatter X-ray detection system. The 6-ch DAQ system is able to store acquired data for 50 μs as 8 bytes and the 6-ch high voltage power supply board provides adjustable power from 0 to 1600 V. Using this detection system, we varied the tube voltage from 80 to 160 kV and observed backscatter X-ray images of two plastic phantoms at 160 kV. The results indicate a need to optimize the speed of the collimator and data acquisition time of the DAQ system to improve image quality. The backscatter X-ray imaging technology exhibits high scalability, making it applicable not only to security screening but also for medical and industrial purposes. [ABSTRACT FROM AUTHOR]

Sampling represents an important step of the procedure to perform authenticity tests by ThermoLuminescence (TL). The result of the test could be compromised if this phase is not correctly carried out. During the drilling, in fact, a local temperature increasing could cause a loss of the luminescence signal. In this paper, the comparison between IR thermography imaging and electrical measurements is shown also in order to validate a specific conceived model. The research is aimed at implementing the procedure used to perform the TL tests with the measurement of the temperature reached during the drilling. The measurements were performed using a pottery sherd simulating the collection step. Results show the validity of the model and provide data useful to optimize the sampling in TL test methodology. [ABSTRACT FROM AUTHOR]

For high rate thermal neutron (and e.g. also synchrotron radiation) detection a PCI data acquisition (DAQ) board for readout of two-dimensional position-sensitive multi-wire proportional chamber (MWPC) detectors with delay line position encoding was developed, and a first series of boards was produced and tested. The MWPC board comprises a deadtime-less 8-channel multihit TDC chip of the F1 type with ∼120 ps LSB, a 40 MHz flash ADC, a FPGA, a FIFO, a 0.9 GFLOP DSP chip TMS320C6711 and a 256 MB histogram memory. For position encoding a position-independent start and four position-dependent stop signals are recorded from the MWPC anode and from either end of X and Y delay lines connected to the MWPC cathodes, respectively. Time-of-flight (TOF) can be measured with reference to a pulsed beam or chopper signal either with ⩾25 ns bin size for TOF ranges of up to ∼420 ms or alternatively with ∼120 ps LSB for ranges ⩽16 ms. The pulse height of the MWPC anode signal is digitized in the flash ADC for neutron-gamma and background discrimination. Hardware event filtering in the FPGA allows event rates up to 1 Mevents/s by disentangling of two events occurring within the delay line time length of e.g. 250 ns. Whilst list mode data are recorded with full rate and full resolution on the host PC disk, 1D–3D histograms can be accumulated online in the on-board HM for a fraction of the data and with reduced resolution. [Copyright &y& Elsevier]

This note explains the basic operation and theory of aliasing, antialiasing and digital filters. The overall purpose of digitizing DAQ systems is to get an accurate representation of a real-world signal derived from sensors or transducers. The importance of digital filters is well established. Digital filters, and more generally digital signal processing algorithms, are classified as discrete-time systems. [ABSTRACT FROM AUTHOR]