Electronic Thesis and Dissertation Repository


Master of Engineering Science


Mechanical and Materials Engineering


Wood, Jeffrey T.

2nd Supervisor

Tutunea-Fatan, O. Remus



The quality of painted surfaces plays an important role in the overall aesthetics of the automotive products. Although a number of quantitative techniques have been developed for this particular type of quality assessment, the solutions proposed so far remain costly and proprietary such that industry continues to rely primarily on qualitative, error-prone human evaluations. To address this, the primary objective of this thesis was to explore the possibility to develop a laser-based technique for the non-tactile quantification of defects in reflective painted surfaces. For this purpose, analytical solutions were formulated to predict the reflection of a laser beam from a known defect and to predict the geometry of an unknown surface from a measured reflection. Furthermore, analysis of the fine structure within the reflected spot indicated a strong correlation with waviness (orange peel) of the reflecting surface.