Research On The Off-line Programming Technolog For Robotic Profile Steel Cutting

Currently, the shape-steel is cut mostly by hand in the domestic shipbuilding industry, thus, the efficiency is low, the consistency of product is difficult to be guaranteed and the working environment is bad. The robot with highly flexible, is suitable for forming automatic product line of shape-steel cutting, so that product efficiency and cutting quality is improved, which is the trend of shape-steel cutting. The core of robot shape-steel cutting system is the off-line programming technology that can achieve the integration of CAD/CAM/Robot. The study of this thesis is off-line programming technology, aiming to solve such problems as the complexity of feature modeling, the bad quality when crossing the edge between steel surfaces, the simple bevel style and so on.Firstly, the overall frame of off-line programming technology in robot shape-steel cutting has been established from the utilization point of view. The focus of this study is the key technology of cutting feature modeling, cutting feature programming, and shape-steel cutting calibration. A feature modeling software has been developed, and the basic features are obtained by importing the DXF file or the mode of drawing. The cutting feature is stored by serial paths, and parametric drawing algorithm has been developed, so that the efficiency of feature has been improved.Secondly, the feature programming is studied. The scene design has been finished by directed acyclic graph, the library of shape-steel which can be maintained is established and the path planning of cutting is carried out. Contour offset intersection algorithm has been developed based on the feature of the groove style of the shape-steel and the consecutive trait of cutting path, realizing the planning of the robot position and pose while cutting the shape-steel with changing groove. On the basis of the offset intersection algorithm, combined with the edge characteristic of the bulb steel and the angle steel, crossing the edge algorithm has been put forward, guaranteeing the smooth cutting of the robot plasma gun cross the edge.Finally, the off-line programming experiments for robotic shape-steel cutting using Motoman UP20 by the way of plasma cutting have been finished. The cutting of various complex graphics has been realized in the flat steel, which proved the feasibility of the parametric programming algorithm. The cutting path with changing bevel has been finished and the groove angle meets the cutting requirements in working conditions. The edge cutting experiment in the angle steel has been carried out, and the move of the robot and plasma gun is smooth. The edge transition is flat, and the shape-steel profile has no mismatch.