ABSTRACT
A novel digital subdividing technique for Moire fringes is put forward in this paper. The digital signal processing method and its software implementation is carried out in a single-chip microprocessor. First, the two digitized sine signals from the two measuring channels are processed by the seuse finding circuit to generate a interrupt pulse signal whose frequency is four times as that of the sine signal. Then in the interrupt service routine, the measured angles are calculated to implement four folds Moire fringes subdivision. At the same time, with the aid of CPU and A/D convertor, a triangular wave signal is calculated based on the two sine signals. Then a novel subdividing technique is utilized to realize twenty folds subdivision. Finally, eighty folds subdivision is applied to the Moire fringes, and the angular measuring precision is up to 1".
