A Signal Normalization Technique for Illumination-Based Synchronization of 1,000-fps Real-Time Vision Sensors in Dynamic Scenes

Sensors

Lei Hou¹  Shingo Kagami² 

[1] Department of System Information Sciences, Graduate School of Information Sciences, Tohoku University, 6-6-01 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579, Japan;

关键词: high-speed vision;    robot vision;    vision chip;    camera synchronization;    phase-locked loop;    signal processing;    visible light communication;    signal normalization;    quadrature detection;   

DOI  :  10.3390/s100908719

来源: mdpi

【 摘 要 】

To acquire images of dynamic scenes from multiple points of view simultaneously, the acquisition time of vision sensors should be synchronized. In this paper, an illumination-based synchronization derived from the phase-locked loop (PLL) mechanism based on the signal normalization method is proposed and evaluated. To eliminate the system dependency due to the amplitude fluctuation of the reference illumination, which may be caused by the moving objects or relative positional distance change between the light source and the observed objects, the fluctuant amplitude of the reference signal is normalized framely by the estimated maximum amplitude between the reference signal and its quadrature counterpart to generate a stable synchronization in highly dynamic scenes. Both simulated results and real world experimental results demonstrated successful synchronization result that 1,000-Hz frame rate vision sensors can be successfully synchronized to a LED illumination or its reflected light with satisfactory stability and only 28-μs jitters.

【 授权许可】

CC BY   
© 2010 by the authors; licensee MDPI, Basel, Switzerland.