标题：A discrete method of sphere-pipe intersecting curve for robot welding by offline programming
作者：Liu Yan; Tang Qiu; Tian Xincheng
作者机构：[Liu Yan; Tian Xincheng] Shandong Univ, Sch Control Sci & Engn, Jinan 250061, Shandong, Peoples R China.; [Tang Qiu] Chongqing Univ, Coll Automat, C 更多
通讯作者：Tian, Xincheng;Tian, XC
通讯作者地址：[Tian, XC]Shandong Univ, Sch Control Sci & Engn, Jinan 250061, Shandong, Peoples R China.
来源：ROBOTICS AND COMPUTER-INTEGRATED MANUFACTURING
关键词：Sphere-pipe intersection; Trajectory calculation; Curve discretization;; Radius of curvature; Robot programming
摘要：The sphere-pipe intersecting curve is a kind of spatial complex curve, which is controlled by robot in the sphere-pipe welding. In this paper, a discrete method for robot welding by offline programming is put forward. To move the robot with the specified curve trajectory, it need to be discretized to generate the robot motion instructions. As the core innovation of this paper, a discrete method of sphere-pipe intersecting curve is given according to the chord error limit and principle of equal arc length, which guarantees the accuracy of robot welding. To achieve this goal, this paper has done the following related works. First, the geometrical model of the sphere-pipe intersection is established, which can cover most of the intersection modes. Second, this paper gives the parameter equations in two different coordinate systems because the expression is very complex. This operation will simplify the subsequent calculations. Although the curve expression is simplified, it is very complicated to find the maximum based on the definition of curvature. After experimental analysis, this paper presents a simple and effective algorithm for the calculation of maximum curvature. Finally, this paper takes the Puma560 robot for simulation, and the simulation results are used to verify the feasibility and effectiveness of our method.