Tactile coordinate measuring machine measurement parameters

Abstract

There are no clear "rules of measuring" for the coordinate measuring machine (CMM). When measuring the diameter or form of a hole or shaft, there are no clear instructions regarding the number of measurement points or setup of filters. In comparison measurements, this problem is not revealed, because a gauge ring is often used in comparison measurements and the gauge rings do not have a form error. When measuring the form error of an ideal hole with a small or large determination of the measuring point, the results yield differences of, at most, a micrometer. The need for measurement rules increases when switching to use product manufacturing information (PMI) data in computer aided design (CAD) models. This thesis focuses on examining parameters that are missing from PMI data: the PMI data missing measurement point quantities per element, scanning speed, and measurement force. In addition, the PMI data also missing parameter values for form filtering and outlier filtering. Based on the existing research literature and standards, there are no clear guidelines for these parameters. In this thesis, the measuring parameters of tactile CMMs were determined. To determine the parameters, varied sizes of the reference normal and one size the test part were measured using three different tactile sensors. As a result of this research, a table of measurement parameters was built. The challenge of the all-encompassing measurement parameter tables was taking into account the differences in the measurement stylus.