A critical look at the coordinate measuring technique

The article presents a critical review of the coordinate measuring technique. It is shown that significant measurement errors may occur due to imprecise formulations in the ISO 10360-2 standard (simplified record related to the best match method, simplified acceptance test, reverification test and interim check), limitation regarding the use of measuring equipment (CMM, PC, IEEE 745, software) and accepted calibration procedure (it is only possible to calibrate half the ball tip probe against half the reference sphere). The article also points out the problems of adequate correction of the ball tip radius, simplifications of the computation procedures, limitations of the correction software (Computer Aided Accuracy), ensuring stable temperature and creating a new system of coordinates (Workpiece Coordinate System). The article discusses the weak points of the coordinate measuring technique which have the largest impact on the measurement results and suggests improvements. The material refers only to contact measurements.

► Limitation of the coordinate measuring technique is analyzed.
► Limitations of the ISO 10360-2 decrease 3-D measurement quality.
► Limitations of the 3-D equipment decrease measurement quality (coordinate measuring machine, Personal Computer, IEEE 745).
► Limitations of the 3-D measurement procedure decrease measurement quality (probe, tip, best-fit methods, error-correction).