Research On Optimization Of Tool Trajectory For Robotic Spray Painting

Painting robot is a kind of important and advanced spray equipment. It is widely used in automotive manufacturing. The figure of a product and the tool parameters can strongly influence the quality of painting. New painting models and tool planning algorithms are active research for many years. The research is supported under JiangSu high tech project fund.The main work of this dissertation consists of four parts as follows:In the first part, the general situation and background about painting robot research and the developing about research are discussed firstly. And then the frame of off-line programming system and the major problems of research are given. Finally some problems, which are studied in this dissertation, are introduced.In the second part, generating paint gun trajectories for plane and regular surfaces are discussed. According to the expressions of plane and regular surfaces, the paint deposition rate function is given. An optimal tool trajectory problem with an optimal film quantity deviation is researched. And the problem is changed to the no constrained optimization problem. The difference quasi-Newton method is adopted here to calculate the values.In the third part, trajectory optimization for painting robot of free-form surfaces is studied. Because the current paint deposition rate function is too complicated, the paint deposition rate function on a plane according to the experiment data is provided. The paint thickness function for free-form surfaces is also given. A multi-objective constraint optimization problem is formulated. An optimal tool trajectory with an optimal time and film quantity deviation is generated. And ideal point method is adopted here to calculate the values by iteration.In the fourth part, trajectory optimization of painting robot for complex curved surfaces is studied. A complex curved surface is divided into several patches by the evaluation function and trajectory optimization for each patch is performed. In order to satisfy the material uniformity requirements, optimization algorithms of the three different cases are developed to integrate the trajectories on the intersecting area of two patches. Finally, a genetic algorithm is developed to solve the trajectory integration problem. And the system which can automatically generate optimized tool trajectory for complex curved surfaces is accomplished.In this dissertation, simulations are made for major design schemes. The results of simulations have shown that the model and the tool planning algorithms are feasible.