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Lewandowski M., Walczak M., Witek B., Rozbicki J., Steifer T., A GPU-Based Portable Phased-Array System with Full-Matrix Capture,
IUS 2018, IEEE International Ultrasonics Symposium, 2018-10-22/10-25, KOBE (JP), DOI: 10.1109/ULTSYM.2018.8579964, pp.1-3, 2018 Abstract: The widely adopted ultrasound Phased-Array (PA) systems for nondestructive testing (NDT) use standard beamforming for line-by-line image creation. The introduction of the new full-matrix capture (FMC) technique enables the implementation of advanced processing algorithms (e.g. the total focusing method, multi-pass adaptive techniques). However, the limited availability of portable PA systems with FMC capabilities prevents widespread introduction. Our goal was to demonstrate the feasibility of a portable PA solution with FMC and advanced processing with the help of a mobile GPU. Using an OEM ultrasound front-end module (us4us Ltd., Poland), we integrated a complete PA system with an embedded Nvidia Tegra X2 module. An external probe adapter enables a direct connection to commercial Olympus-NDT PA probes with up to 128-elements (32-element active RX aperture). The system is fully programmable, both in the front-end (TX/RX schemes, acquisition parameters), as well as in the digital signal processing chain. Raw RF data is acquired and transferred to mobile GPU memory for processing. The algorithm can be conveniently implemented using a standard Nvidia CUDA toolkit. We implemented real-time B-mode imaging with the total focusing method for demonstration purposes. The presented all-in-one system is a fully flexible tool for the research and evaluation of novel Phased-Array FMC methods and complex signal processing algorithms. An extended programmability and real-time access to raw channel data allows to create custom solutions specifically dedicated to any one NDT application. Mobile GPU parallel processing provides a strong enough performance for real-time imaging. Its small size and low-power consumption make the system an ideal candidate for a portable industrial flaw detector with advanced processing. Affiliations:
Lewandowski M. | - | IPPT PAN | Walczak M. | - | IPPT PAN | Witek B. | - | IPPT PAN | Rozbicki J. | - | IPPT PAN | Steifer T. | - | IPPT PAN |
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Rozbicki J., Witek B., Steifer T., Lewandowski M., Doppler-based blood pressure measurement system for patients supported by a continuous-flow rotary left ventricular assist device,
IUS 2017, IEEE International Ultrasonics Symposium, 2017-09-06/09-09, Washington (US), DOI: 10.1109/ULTSYM.2017.8091990, pp.1-4, 2017 Abstract: The medical management of patients with continuous-flow left ventricular assist devices (LVADs) requires frequent measurement and analysis of various physiological parameters. Among the most important is blood pressure (BP), which cannot be reliably measured by the standard oscillometric method because of an impaired pulsation due to continuous flow. The objective of this work is to show the feasibility of ultrasound-based BP measurement in a portable, easy to use device for patients with LVAD in home-based rehabilitation environments, enabling long-term remote monitoring. We have implemented a BP measurement system which uses continuous wave (CW) Doppler ultrasound for blood flow detection. The system is based on a standard cuff design with custom analog CW circuitry connected to a high-performance, low-power 32-bit microcontroller (ARM Cortex-M7). The uC is responsible for system control, as well as Doppler signal acquisition and processing. A dedicated ultrasound probe equipped with an elastic strap is placed over the radial artery. In the target solution, the cuff pressure and CW signal will be analyzed in real-time to provide systolic and/or mean blood pressure. At present, we have acquired raw signals for off-line analysis. The system was tested in clinical experiments both on healthy patients and patients with three types of commercially available LVADs (HeartWare, HeartMate II and HeartMate III). The observed morphology of Doppler signals in patients with LVADs was much more variable between patients and pumps. In most cases, we were able to estimate the systolic pressure, but the measurement of diastolic pressure was not conclusive. We observed variable blood flow patterns generated by the Lavare cycle (a periodic speed modulation feature of some LVADs), which further complicates the estimation. A prototype of an automatic BP measuring device for patients with rotary LVADs has been demonstrated. In the next step, we are planning an animal validation study with invasive blood pressure monitoring Keywords: Biomedical monitoring, Doppler effect, Blood pressure, Blood, Pressure measurement, Ultrasonic variables measurement, Standards Affiliations:
Rozbicki J. | - | IPPT PAN | Witek B. | - | IPPT PAN | Steifer T. | - | IPPT PAN | Lewandowski M. | - | IPPT PAN |
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Kustroń P.♦, Korzeniowski M.♦, Lewandowski M., Witek B., Rozbicki J., A High Frequency Ultrasonic Imaging of Welded Joints,
IUS 2016, IEEE International Ultrasonics Symposium, 2016-09-18/09-21, Tours (FR), DOI: 10.1109/ULTSYM.2016.7728848, pp.1-4, 2016 Abstract: The paper presents chosen results obtained during the investigation of welded joints (laser, spot and friction) tested using acoustic microscopy method. Detection of welds properties and the defects strongly depends on ultrasonic transducer’s parameters. For the purpose of this research a prototype hardware setup was built – enabling evaluation of various types of ultrasonic probes. The system can be easily adjusted to the geometry of an object and is well equipped with appropriate software for the analysis and processing of images such as B-scan or C-scan. The setup enables determination of welds geometry, in particular the depth of the weld penetration in some cases. Keywords: spot welds, high frequency ultrasonic imaging Affiliations:
Kustroń P. | - | other affiliation | Korzeniowski M. | - | other affiliation | Lewandowski M. | - | IPPT PAN | Witek B. | - | IPPT PAN | Rozbicki J. | - | IPPT PAN |
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