Frame Synchronization of High-Speed Vision Sensors with Respect to Temporally Encoded Illumination in Highly Dynamic Environments

Sensors

Lei Hou¹  Shingo Kagami² 

[1] Department of Automation, Shanghai Jiao Tong University, and Key Laboratory of System Control and Information Processing, Ministry of Education of China, Shanghai 200240, China;Graduate School of Information Sciences, Tohoku University, 6-6-01 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579, Japan; E-Mails:

关键词: robot vision;    vision chip;    camera synchronization;    visual feedback control;    phase-locked loop;    signal normalization;    quadrature detection;    intelligent coding;    Manchester encoding;   

DOI  :  10.3390/s130404102

来源: mdpi

【 摘 要 】

The authors propose a Manchester Encoding inspired illumination modulation strategy to properly index the temporally-aligned vision frames, which are successfully synchronized by the LED reference signal. Based on signal normalization, Manchester Encoded reference signals carry temporal information owing to serial communication and thus can timestamp the output vision frame. Both simulated and experimental results show satisfactory robustness to various disturbances, such as dynamic targets, fluctuant optical intensity, and unfixed cameras, etc. The 1,000 Hz vision sensor is locked to 500 Hz temporally modulated LED illumination with only 24 μs jitters. This result is believed to be applicable to low-cost wireless vision sensor network.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.