A method and a computer program are developed for modeling of spray painting process, simulation of robotic spray painting, off-line programming of industrial robots and paint thickness measurement for painting of curved surfaces. The computer program enables the user to determine the painting strategies, parameters and paths. Surface models of the parts that are to be painted are obtained by using a CAD software. For paint thickness measurements, probe of the coating thickness measurement gage is attached to the wrist of the robot by using a feedback/safety adapter designed and manufactured for this purpose. Thicknesses are measured and transferred to the computer automatically. Then, obtained thickness data is processed and comparisons between simulated and measured thicknesses are made.