Path generation for planar spray painting

An algorithm is developed here for the generation of paint paths based upon a geometric model of the workpiece. The algorithms are applicable to planar workpieces defined by contiguous line segments.

A process cost model is developed to quantify the economic cost of spraying an individual workpiece. The model includes the cost of the paint itself, operating and maintenance costs of the painting system, and costs for filtration and disposal of waste paint.

An algorithm is presented for minimizing the process cost model. The algorithm illustrates that minimum process cost is obtained with the highest possible spray gun velocity, subject to the constraints of maximum paint flowrate and required paint thickness, and the spray pattern adjusted for minimum aspect ratio.

For a given deposition profile the uniformity of paint thickness over consecutive spray passes is determined by the overlap between them. Three measures for paint thickness uniformity are presented. For the elliptical spray pattern used here the optimum uniformity occurs between 16-18 percent overlap, depending which measure of uniformity is used.

The algorithms presented here have been written in the 'C' programming language and can be executed within the AutoCAD environment. (Abstract shortened by UMI.)