Analysis of the measurement uncertainty of a positional error calibrator based on a laser interferometer

A positional error calibrator for evaluating the positioning accuracy of 6-dof simulation system under dynamic conditions has been developed. It is based on the Hewlett Packard 5529A laser interferometer, which is capable of performing dynamic calibration. This laser interferometer measures the position of the slide as it moves continuously along the simulation system axis under test. The data are collected on a position basis by triggering the laser interferometer from a position-based reference signal. A software package has been developed for data acquisition and presentation of the positional errors in accordance with ISO 230-2 standard. This paper deals with the evaluation of the measurement uncertainty of this positional error calibrator. In order to assess the total measurement uncertainty of this calibrator, an analysis of the individual errors that make up the accuracy and repeatability error budgets has been carried out. These error budgets consist of three components. This uncertainty analysis was carried out when this calibrator was used to assess the positional errors of a 6-dof simulation system.