AN OPTICAL DISPLACEMENT METER BASED ON A LIGHT-TO- FREQUENCY CONVERTER

O. Postolache, M.D. Pereira, P. Girão, M. Cretu

Abstract

This paper proposes a contactless displacement measurement system based on a temperature compensated light-to-frequency (<i>L</i>/<i>F</i>) converter. The optical displacement sensor is represented by the <i>L</i>/<i>F</i> converter excited by a LASER beam. To compensate the temperature drift error of the displacement sensor, an additional temperature measurement system based on a temperature transducer is required. The processing of the data delivered by the sensors is on-line performed using a neural algorithm implemented on a Digital Signal Processor. The Artificial Neural Network architecture used in the present application is Multiple Inputs – Single Output (MISO) type, and the output of the network represents the displacement value after an on-line temperature correction. In the calibration phase of the displacement measurement system a closed-loop motorised linear actuator controlled by a plug-in-PC motion board is added to the system.

Keywords

displacement measurement, optical transducer, error compensation

Download

IMEKO-WC-2000-TC2-P050.pdf

DOI

-

IMEKO TC

TC2 - Photonics

Back to the proceedings