Abstract
A velocity and position measurement system based on the method of convolution integral with spatial weighting functions is proposed. The proposed method is very useful to give many kinds of spatial filtering characteristics to a TV camera in parallel, because arbitrary spatial filtering characteristics can be realized by simple electronic circuits. In the proposed measuring system, one TV camera works as three pairs of sinusoidal spatial filters, the periods of which are different from each other. From the geometric relation between two outputs of one pair of sinusoidal spatial filters, a velocity is obtained by a simple argorithm, and a position is obtained from the difference between the outputs of two pairs of spatial filters. All of the spatial filters are made of the digital circuits which include six DSPs, while the two signal processing circuits to calculate the velocity and position are made by the analogue circuits. In order to realize the real time measurement, all of the signal processing which must be done in spatial domain are substituted by the signal processing done in time domain. As the results of some experimental confirmations, it became clear that the proposed measuring system is accurate enough for practice and has wide applications.
