Robot-assisted painting system for bolt-nut pairs

Bolt-nut pairs painting of aerostructures, in particular legacy products, relies heavily on the skill or rather craftsmanship of the human operator. This process is time-consuming while automated operations with industrial robots can be a more efficient solution. This paper describes the development of such an automated bolt-nut pair painting system for a small parts assembly line. In this paper, a low-cost and flexible solution for automated bolt-nut pair painting using a painting dabber and machine vision system is proposed. A Sense 2 camera is used to capture the 3D model of the parts, and an ABB industrial robot YuMi is programmed to implement the painting automatically. A specific nozzle for the dabber is designed to apply paint on bolt-nut pairs. The results shows that the location of every bolt-nut pair is found successfully, and the accuracy of the normal vectors is enough for robot-assisted painting work.