Digital synchronous measurement method for two-dimensional in-plane displacement using check-code

Abstract

The measurement of two-dimensional displacement is an essential aspect of ultra-precision manufacturing and product design. This paper introduces an innovative method that uses a four-reader probe and a group of check codes to achieve digital synchronous measurement of translational and rotational displacement. The measuring principle and two-dimensional coding method are modelled first, and several reader-code combinations are proposed. And then, the study conducts numerical simulations to investigate the effect of different factors on measurement accuracies, such as check code size, machining tolerance, and reader resolution, and the method’s accuracy and performance are evaluated based on the error distribution to determine the optimal system parameters for various applications. A specialized lab experiment is conducted to validate the accuracy and reliability of the proposed method. In conclusion, the proposed method is innovative and practical, which realizes the synchronous measurement of two-dimensional in-plane displacement instead of a simple combination of two one-dimensional sensors.