The CAM System for the Arc-welding Robot for Hull Sub-assemblies

Abstract

In order to extend the applicable range from the parallel parts to the non-parallel parts of hull structures, a new CAM system for the arc-welding robot has recently been developed.When automatic arc-welding is extended to all the non-parallel hull part workpieces of different shapes, the new CAM system is required to respond flexibly to the alterations of production order, shapes and the laying positions of related workpieces, without taking much time for programming. Satisfying these needs, the following means has been studied for the new system.(1) The new CAM system supplies a task level welding program to the robot controller, which, simultaneously generates every robot motion. Consequently, when it becomes necessary to alter the laying positions of workpieces due to the change of the production order, the robot can react freely to the alterations.(2) For saving programming time and for simplifying the operation, the system of a human interface with an interactive mode is adopted using graphic displays. Operation guides of the system and those commands for selection are both shown on the graphic displays.(3) For saving time and avoiding errors, the data-base of the hull structures is used for programming.(4) A micro computer is provided at the control room in the sub-assembly shop for editing, alterating and maintaining the welding programs.This new function enables the system to react flexibly to the alterations of design and production order.It is estimated that utilization of the new CAM system reduces programming time by 2/3.Experimental calcurations on the economy of the robot based on the actual record of programming and welding time has confirmed that it is possible to maintain an economical advantage even in the case of the robot being applied to workpieces of various shapes.The arc-welding robot for hull sub-assemblies can be effectively used on non-parallel parts of hull structures by employing the new CAM system.This new system offers full automation potential for every welding activity on the sub-assembly line of hull structures.