Optimal Spraying Path Generation for Complex Concave Surfaces

Automatic spray path planning is crucial to successfully automate spray coating processes. Several methodologies have been developed for optimal path generation. However, few have been reported to cope with complex and concave surfaces such as those encountered in semi-permanent molds. This work proposes a framework for automatic spray path planning for complex concave surfaces. It employs a segmentation algorithm and two-dimensional cubic Bézier curves to generate spraying strokes without loops and collisions with the surface, and with limited curvature. This methodology was tested on a surface that embodies the main characteristics of real semi-permanent molds employed on gravity die casting achieving low coating thickness error and high coverage of the surface.