Automatic trajectory generation for metal surface droplet coloring

Abstract

Abstract In this study, an automatic trajectory-generation algorithm is proposed to achieve uniform droplet coloring on the metal surfaces. First, by taking into account key parameters such as contact angle, surface tension, and droplet mass, the coloring technology was analyzed, and the size of a droplet was estimated. Then, the zones of the same color as those in the color reference pattern image were extracted and grouped by pixel searching. Zone erosion and pixel points-sorting algorithms were used to select trajectory points successively. Subsequently, nonuniform rational B-splines (NURBS) curves were used to interpolate the sorted trajectory points and generate G1 continuous curves. Finally, the continuous curves were discretized, and coloring trajectories were generated. Experimental results showed that the proposed algorithm achieved automatic color block extraction, arbitrary trajectory generation, and uniform surface coloring.