Research On Spray Gun Trajectory Generation For Spray Painting Robots

Compared with teaching programming,off-line programming used to plan spray painting robot trajectory in spray coating process can avoid endangering worker's health effectively,improve spraying quality and realize robot auto-spray paint.The spray gun trajectory generation module to plan robot trajectory is the core one of the off-line programming system for spray painting robots.In this paper,the method of spray gun trajectory generation is researched,which provides a new approach for the development and application of off-line programming system.The main contents and contributions of this paper are summarized as follows:1.In order to effectively utilize workpiece CAD models of different data formats for off-line programming system to plan spray painting robot trajectory,a technique of acquiring the spray gun trajectory based on STL model is provided. Firstly,the normal vectors of the vertexes are estimated.Secondly,slicing process is applied to the STL model in order to obtain the intersection points,and coating track is obtained by the direction arrangement of the intersection points.Then the normal vectors of the intersection points are calculated.Lastly,the spray gun trajectory is formed through the intersection points offsetting the distance between spray gun and workpiece along their normal vectors.2.In order to effectively utilize workpiece point cloud for off-line programming system to plan spray painting robot trajectory,a technique of acquiring the spray gun trajectory based on point cloud is provided.Firstly,the point cloud data are obtained by scanning the surface of workpiece.Secondly, slicing process is applied to the point cloud data,and coating track is obtained by the direction arrangement of slice data.Then the normal vectors of the sampling points are estimated.Lastly,the spray gun trajectory is generated through the sampling points offsetting the distance between spray gun and workpiece along their normal vectors.3.An architecture of the spray gun trajectory generation system for spray painting robots based on STL model and point cloud is presented,and a spray gun trajectory generation prototype system is developed to validate the related method. The feasibility and validity of method,which generates spray gun trajectory,is proved by an example.