Research On Off-line Programming System Of Industrial Robot For Complex Surface Processing

Industrial robot technology is being widely used, and increasingly being applied to theprocessing of surfaces and curves, such as surface spraying or rubber coating. The teachingand playback operation of traditional industrial robots has great limitation, and off-lineprogramming technology has shown great advantages, which can directly create a worktrajectory of industrial robot form3D(three-dimensional) CAD model and complete theprocessing operations of complex surfaces and curves. The paper accordingly launched astudy, namely: off-line programming system of industrial robot for complex surfaceprocessing. This thesis was supported by Guangdong Province Strategic Emerging IndustriesProjects(2011A091101001), and the main research works are as follows:The paper carried out the study of a trajectory generation method of complex surfacebased on STL (Stereolithography)file. Created the STL file which contains a set of triangularfacets by a3D(three-dimensional) CAD model. Generated a set of data points by usingmultiple parallel plane intersect with triangular facets for the intersection. The motiontrajectory of robot can be obtained by optimizing and sorting the data points. The simulationanalysis concluded that the method can be used to create the machining trajectory generationof irregular complex surface.The paper carried out the study of NURBS(Non-Uniform Rational B-Splines) curveinterpolation algorithm based on chord error. NURBS curves in3D(three-dimensional) CADare widely used in the expression of complex surface. Generated the set of interpolationpoints based on chord error constraints. Used look-ahead acceleration deceleration controlalgorithm to smooth feed rate. Thereby, reduced the vibration in the process of NURBS curveinterpolation and improved the processing quality.The paper carried out the study of a trajectory generation method of NURBS surfacebased on IGS file. IGS file in the CAD/CAM software as the initial graphics exchangespecification type2D/3D vector graphics file, contains the mathematical parameters ofNURBS curve and surface. Mathematical parameters is extracted from the IGS file ofNURBS surface. Calculated node parameter of NURBS surface using NURBS curveinterpolation algorithm. Calculated the set of interpolation points according to node parameter.The machining motion trajectory of NURBS surface can be obtained based on the set ofinterpolation points.The paper constructed the off-line programming experiment platform of industrial robot for complex surface processing. The experiment platform control system, which usingPC-BASED architecture, can synchronously control6AC servo motor. According to theprocessing object for the two kinds of complex surface, completed the experimentalverification of the above algorithm of chapters on the platform. Experimental results showthat the above algorithm is very effective.The innovative achievements in this paper: proposed a trajectory generation method ofcomplex surface based on STL file and apply it to the off-line programming system ofindustrial robot. Presented Look-Ahead acceleration deceleration control algorithm.Smoothed feed rate and reduced the vibration in the process of NURBS curve interpolation.proposed a trajectory generation method of NURBS surface based on IGS file and apply it tothe off-line programming system of industrial robot.Research results in this paper can be applied to the processing of complex surface byindustrial robot and promote application technology of industrial robot in China.