Dynamic Error Characterization for Non-Contact Dimensional Inspection Systems

Abstract

High-precision non-contact dimensional inspection systems typically utilize high-precision motion stages to manipulate the sensor. Such motion stages are susceptible to position errors, which need to be characterized. While geometric and thermal errors can be characterized and compensated, compensation of dynamic errors is a challenging task. This paper presents a method for dynamic error characterization that is significantly different from dynamic error characterization on contact-based systems. A mathematical model to translate the vibrations on the sensor to the measurement errors on the part is presented. Through experiments on a four-axis system, a relationship between sensor motion speed, sampling frequency, and measurement accuracy is derived. The results of the experiments are used to describe the selection of optimal operating parameters for best accuracy and least uncertainty.