DocumentCode :
2410570
Title :
A real-time micro-PIV system using frame-straddling high-speed vision
Author :
Kobatake, Motofumi ; Takaki, Takeshi ; Ishii, Idaku
Author_Institution :
Hiroshima Univ., Hiroshima, Japan
fYear :
2012
fDate :
14-18 May 2012
Firstpage :
397
Lastpage :
402
Abstract :
In this study, we introduce a novel concept of real-time microscopic particle image velocimetry (micro-PIV) for high-speed microchannel flows in a lab-on-a-chip using a frame-straddling high-speed vision system with two camera inputs; it can synchronize two camera inputs with the same view field with a time delay on a submicrosecond time scale. To improve the measurable range of velocity in microchannel flow observation, we propose a variable-frame-straddling optical flow (VFS-OF) algorithm that can simultaneously estimate the microchannel flow distribution as gradient-based optical flows using frame-straddled images from the two camera inputs; their frame-straddling time is determined by the amplitude of the estimated optical flow to avoid large image displacements between frames that often generate serious errors in optical flow estimation. We built a real-time micro-PIV system by software-implementing the VFS-OF algorithm in a high-speed vision system with two frame-straddled cameras; it can execute real-time video processing and recording of 512×512-pixel images at 2000 frames per second for the two cameras and control their frame-straddling time from 0 to 0.5 ms with 9.9-ns steps. Our micro-PIV system can estimate the velocity distribution of high-speed microchannel flows at 1 m/s or more in real time by controlling the frame-straddling time. Experimental results were performed for microfluidic flows on microchannels with widths of hundreds of micrometers to verify the performance of our micro-PIV system based on the VFS-OF algorithm.
Keywords :
computational fluid dynamics; flow measurement; gradient methods; image sensors; image sequences; lab-on-a-chip; microchannel flow; velocimeters; frame-straddled cameras; frame-straddled images; frame-straddling high-speed vision system; gradient-based optical flows; high-speed microchannel flows; high-speed vision system; lab-on-a-chip; microchannel flow distribution; microfluidic flows; optical flow estimation; real-time micro-PIV system; real-time microscopic particle image velocimetry; real-time video processing; submicrosecond time scale; time delay; variable-frame-straddling optical flow algorithm; Cameras; High speed optical techniques; Microchannel; Optical imaging; Optical variables measurement; Real time systems; Vectors;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Robotics and Automation (ICRA), 2012 IEEE International Conference on
Conference_Location :
Saint Paul, MN
ISSN :
1050-4729
Print_ISBN :
978-1-4673-1403-9
Electronic_ISBN :
1050-4729
Type :
conf
DOI :
10.1109/ICRA.2012.6224821
Filename :
6224821
Link To Document :
بازگشت