Fundamental Study on Optical Rotating Field

摘要

Recently the needs for distance and attitude measurements are increasing in material handlings by robots or flexiblemanufacturing systems, et al. In these measurements, optical or super sonic methods are mainly used since non contact measurements are desirable.This paper proposes an idea of signal field which can be applied to various kinds of active measurement. First, both the generating method and the properties of rotating signal fields are considered, and an optical rotating field is composed experimentally by infra-red light emitting diodes IR-LEDs (940nm wave length) which are located quadrilaterally. On the other hand, the detecting system is set on a plane, and is composed of five photo-diodes; four of them are positioned at each corner of a square on the plane, and the remainder is at the center of the square.A signal processing method is proposed for obtaining six variables which are used to determine the position and the attitude, then the methods are experimentally examined.With compensating the angular sensitivity characteristics of the sensors, the following experimental results are obtained;(1) As for the measurent of positions, the measuring ranges are from 500mm to 750mm (Z-direction), from-100mm to+100mm (both X and Y directions), and those absolute errors are within±5mm.(2) As for the measurement of rotating angle, the measuring range is from-180 degrees to+180 degrees, and its absolute error is within ±5 degrees.