Composite NDE using full-field pulse-echo ultrasonic propagation imaging system

2016 ◽  
Author(s):  
Seung-Chan Hong ◽  
Jung-Ryul Lee ◽  
Jongwoon Park
Keyword(s):  
Imaging System ◽  
Field Pulse ◽  
Full Field ◽  
Ultrasonic Propagation ◽  
Pulse Echo

scholarly journals Detectable Depth of Copper, Steel, and Aluminum Alloy Plates with Pulse-Echo Laser Ultrasonic Propagation Imaging System

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1607
Author(s):  
Dong-Il Kim ◽  
Ku-Rak Jung ◽  
Yoon-Soo Jung ◽  
Jae-Yeol Kim
Keyword(s):  
Aluminum Alloy ◽  
Imaging System ◽  
Front Surface ◽  
Acoustic Properties ◽  
Laser Ultrasonic ◽  
Excitation Laser ◽  
Scan Data ◽  
Ultrasonic Propagation ◽  
Hot Rolled ◽  
Pulse Echo

Pulse-echo laser ultrasonic propagation imaging is a nondestructive testing technique developed for composite materials and aluminum alloys used in aerospace. Although this method has been in usage for a considerable time, information of the detectable depth and the relationship between ultrasonic frequencies and the acoustic properties of metals is not readily available. Therefore, we investigate the A-scan and C-scan ultrasonic testing data of aluminum alloy, hot rolled steel, stainless steel, and copper alloy, which are used in aircraft bodies, frameworks, and gas pipelines. Experiments are performed with the pulse-width and excitation laser power fixed at 32 ns and approximately 4 W, respectively. The metal specimens include 24 artificial cylindrical defects with a diameter of 5 mm, located at depths of 1–12 mm on the front surface. The A-scan and C-scan data obtained at room temperature indicate the detectable depth for metals via the pulse-echo laser ultrasonic propagation imaging technique.

Development of pulse-echo ultrasonic propagation imaging system and its delivery to Korea Air Force

2017 ◽  
Author(s):  
Hasan Ahmed ◽  
Seung-Chan Hong ◽  
Jung-Ryul Lee ◽  
Jongwoon Park ◽  
Jeong-Beom Ihn
Keyword(s):  
Air Force ◽  
Imaging System ◽  
Ultrasonic Propagation ◽  
Pulse Echo

Long distance laser ultrasonic propagation imaging system for damage visualization

2011 ◽  
Vol 49 (12) ◽  
pp. 1361-1371 ◽  
Author(s):  
Jung-Ryul Lee ◽  
He-Jin Shin ◽  
Chen Ciang Chia ◽  
Dipesh Dhital ◽  
Dong-Jin Yoon ◽  
...  
Keyword(s):  
Imaging System ◽  
Long Distance ◽  
Laser Ultrasonic ◽  
Ultrasonic Propagation ◽  
Damage Visualization

scholarly journals Experimental study of the dynamic behaviour of High Performance Concrete (HPC) under tensile loading

2018 ◽  
Vol 183 ◽  
pp. 02043 ◽  
Author(s):  
Bratislav Lukić ◽  
Dominique Saletti ◽  
Pascal Forquin
Keyword(s):  
High Speed ◽  
High Performance ◽  
High Performance Concrete ◽  
Imaging System ◽  
Spall Strength ◽  
High Speed Imaging ◽  
Dynamic Tensile Strength ◽  
Full Field ◽  
Local Point ◽  
Measurement Results

This paper presents the measurement results of the dynamic tensile strength of a High Performance Concrete (HPC) obtained using full-field identification method. An ultra-high speed imaging system and the virtual fields method were used to obtain this information. Furthermore the measurement results were compared with the local point-wise measurement to validate the data pressing. The obtained spall strength was found to be consistently 20% lower than the one obtained when the Novikov formula is used.

Multi-kernel deconvolution for contrast improvement in a full field imaging system with engineered PSFs using conical diffraction

2018 ◽  
Vol 100 ◽  
pp. 161-169 ◽  
Author(s):  
Jose M. Enguita ◽  
Ignacio Álvarez ◽  
Rafael C. González ◽  
Jose A. Cancelas
Keyword(s):  
Imaging System ◽  
Full Field ◽  
Field Imaging

scholarly journals Development of a Compact,  Configurable, Real-Time Range  Imaging System

2021 ◽  
Author(s):  
◽  
Adrian Peter Paul Jongenelen
Keyword(s):  
High Speed ◽  
Imaging System ◽  
Modulation Frequency ◽  
Image Sensor ◽  
Measurement Precision ◽  
Operating Parameters ◽  
Range Imaging ◽  
Field Range ◽  
Full Field ◽  
Precision And Accuracy

<p>This thesis documents the development of a time-of-flight (ToF) camera suitable for autonomous mobile robotics applications. By measuring the round trip time of emitted light to and from objects in the scene, the system is capable of simultaneous full-field range imaging. This is achieved by projecting amplitude modulated continuous wave (AMCW) light onto the scene, and recording the reflection using an image sensor array with a high-speed shutter amplitude modulated at the same frequency (of the order of tens of MHz). The effect is to encode the phase delay of the reflected light as a change in pixel intensity, which is then interpreted as distance. A full field range imaging system has been constructed based on the PMD Technologies PMD19k image sensor, where the high-speed shuttering mechanism is builtin to the integrated circuit. This produces a system that is considerably more compact and power efficient than previous iterations that employed an image intensifier to provide sensor modulation. The new system has comparable performance to commercially available systems in terms of distance measurement precision and accuracy, but is much more flexible with regards to its operating parameters. All of the operating parameters, including the image integration time, sensor modulation phase offset and modulation frequency can be changed in realtime either manually or automatically through software. This highly configurable system serves as an excellent platform for research into novel range imaging techniques. One promising technique is the utilisation of measurements using multiple modulation frequencies in order to maximise precision over an extended operating range. Each measurement gives an independent estimate of the distance with limited range depending on the modulation frequency. These are combined to give a measurement with extended maximum range using a novel algorithm based on the New Chinese Remainder Theorem. A theoretical model for the measurement precision and accuracy of the new algorithm is presented and verified with experimental results. All distance image processing is performed on a per-pixel basis in real-time using a Field Programmable Gate Array (FPGA). An efficient hardware implementation of the phase determination algorithm for calculating distance is investigated. The limiting resource for such an implementation is random access memory (RAM), and a detailed analysis of the trade-off between this resource and measurement precision is also presented.</p>

Sign in / Sign up

Export Citation Format

Share Document