Laser method for dimensional measurement in projectile production
Virpi, Juha-Matti (2017)
2017
Materials Engineering
Teknisten tieteiden tiedekunta - Faculty of Engineering Sciences
This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
Hyväksymispäivämäärä
2017-12-07
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tty-201711172169
https://urn.fi/URN:NBN:fi:tty-201711172169
Tiivistelmä
Laser measurement technology is high-speed and flexible nondestructive testing method. Dimensional laser measurement is studied in this master’s thesis. Laser triangulation is laser measurement technology which can be used in various applications. Laser triangulation is based on basic triangulation method. With triangulation it is possible to determine distance between three points if at least one side and two angles are known. Laser scanning system studied in this thesis is based on laser triangulation.
Measurement uncertainty can be found in every measurement. The most important thing is to know what the measurement uncertainty of used application is. Two types of measurement uncertainties exist: type A which are statistically found uncertainties and type B which are found experimentally or from manufacturer’s datasheets. Measurement uncertainty components and distribution factors for the uncertainty components were collected for the laser scanning system to be used in measurement uncertainty calculations.
In this master’s thesis laser scanning system used in projectile cavity dimensional measurement was studied. There have been problems with the calibration and the accuracy of the system. Calibration problems were solved and the measurement uncertainty of the laser scanning system was calculated. The calculation of measurement uncertainty included repeatability and reproducibility study. To compare calculated measurement uncertainty of laser scanning system to the previously used projectile cavity measuring method, measurement uncertainty of slide caliper was calculated. Measurement uncertainty of laser scanning system was found out to be better than measurement uncertainty of slide caliper. Moreover laser scanning system gives much more information about the shape and real dimensions of the cavity than slide caliper measurement. As a result of this study the accuracy requirements for this application were fulfilled by the laser scanning system.
Measurement uncertainty can be found in every measurement. The most important thing is to know what the measurement uncertainty of used application is. Two types of measurement uncertainties exist: type A which are statistically found uncertainties and type B which are found experimentally or from manufacturer’s datasheets. Measurement uncertainty components and distribution factors for the uncertainty components were collected for the laser scanning system to be used in measurement uncertainty calculations.
In this master’s thesis laser scanning system used in projectile cavity dimensional measurement was studied. There have been problems with the calibration and the accuracy of the system. Calibration problems were solved and the measurement uncertainty of the laser scanning system was calculated. The calculation of measurement uncertainty included repeatability and reproducibility study. To compare calculated measurement uncertainty of laser scanning system to the previously used projectile cavity measuring method, measurement uncertainty of slide caliper was calculated. Measurement uncertainty of laser scanning system was found out to be better than measurement uncertainty of slide caliper. Moreover laser scanning system gives much more information about the shape and real dimensions of the cavity than slide caliper measurement. As a result of this study the accuracy requirements for this application were fulfilled by the laser scanning system.