Imaging systemdesign formeasuring pointing error of solar trackingAuthor(s): LiHui-Duan
Imaging system design is presented in this paper for measuring pointing error of solar tracking for a long time. An industrial computer with large hard disk is chosen as central processing unit instead of a digital signal processor for storing and processing massive image data of the sun. An advantage of the proposed imaging system is that it stores all the sun images grabbed. The imaging system consists of an optical head, A CCD image sensor, SAA7111A, FPGA, EZ-USB 8051 microcontroller, an industrial computer and so on. The optical head is constructed with a pinhole aperture and no lens is used for simplification. Suns image formed by the optical head is detected by the CCD image sensor. Analogue signals from CCD image sensor are converted in to digital ones by SAA7111A. SAA7111A is configured and controlled by FPGA. Digital image signals are finally sent to the industrial computer via EZ-USB 8051 microcontroller. Experiments have indicated that the proposed imaging system is able to obtain and store massive image date of the sun.