Camera movement control system in fatigue crack propagation test based on NI technology

ZHOU Yin,GAO Hongli, ZHONG Jianfei， SHEN Shanshan， YUN Yan

（Key Laboratory of E&M， Ministry of Education & Zhejiang Province,
Zhejiang University of Technology, Hangzhou 310014, China）

Abstract:  Aiming at the problem of online fatigue crack detection, a camera motion control method applied to the fatigue crack propagation test based on NI technology was suppliedThe system includes CCD cameras, lenses, PTZ, motion control card PCI7334, a lighting device, image acquisition card PCI1410, computer with the image processing software and PC movement control software In accordance with the camera movement requirements during image acquisition, the motion control structure was designed, fouraxies movement control application software was developed with NI Motion tool The experiment results show that the single step/continue movement and automatic tracking of the cameras are performed during the fatigue test and the camera position control accuracy reaches 005 mm

Key words: fatigue crack propagation test；charge coupled device(CCD)；stepping motor；motion control；NI Motion