R-LAT 3D Probe를 이용한 Robotic Drilling System 개발에 관한 연구

Abstract

A Study on the Development of Robotic Drilling System using the R-LAT 3D Probe

Tae Hwa Kim Department of Microbiology, The Graduate School, Pukyong National University Abstract There is an increasing demand from industry for intelligent robot engineering solutions, such as advanced robot drilling systems, smart calibration systems and tightly integrated robot systems in the manufacturing process. Because multi articulated industrial robots have a high flexibility and can produce the high range of working space, they are widely used in the welding, painting, assembly and material handling processes in the shop flow with high variety and complexity processes. but they are not generally used in cutting processes except only using in the aerospace manufacturing processes. The structure of multi articulated industrial robot has generally six joints, moving by servo-motor and doing a form of rotation or shaking motion. So they have an abundant characteristics of high flexibility and working space as like arms and legs of person. But they have a low stiffness at the joints, so cutting processes are not even tried at them in the machine shop floor. The aerospace manufacturing processes is composed with heavy, medium, and finishing cutting processes. Although their depth of cut is different each other as the machine tools and work materials, generally speaking the heavy cutting is a large amount of depth of cut, and the medium is a middle amount of it, and finishing is a quite small amount of it. In case of aluminium materials finishing cutting is especially used to carry out below 0.25mm depth of cut in the aviation industry. According to the above points this research has been started five years ago in order to widen the application range of multi articulated industrial robots, and aid the enterprises wanting a business rationalization through raising up the productivity by the shot cut of workpiece setting time, as realizing the aerospace manufacturing processes with high flexibility and working space at the multi articulated industrial robots. Proposed this research solution is only needed a small set of measurements with significantly little time & effort compared to those of other robot calibration & robot teaching methods in the aviation industry. We developed a new way to integrate metrology system and robot system. The iGPS system is a laser based system with vast freedom to configure the system based on user’s needs. One of basic elements is acquiring three-dimensional point on several critical locations. Those three-dimensional points can be measured as an integrated system or can be measured as a manual contact-type measurement by a user. A three-dimensional probe is introduced as user hold the probe in his hand and moves the probe tip over the object. The X, Y, and Z coordinates of the probe tip are measured in real time with high accuracy. In this research, a new way of improve robot system calibration & an intelligent robot teaching application are introduced by implementing a three-dimensional measurement system for measuring position and total orientation of an object with motions in up to six degrees of freedom. The general concept and kinematics of the metrology system as well as the derivations of an error budget for the general device are described. And then, next to investigate the possibility regarding the aerospace manufacturing processes at an intelligent robot, the robot being set the drilling head on the wrist of an intelligent robot of the FANUC company is fabricated, and the structural analysis by CATIA V5, and the real drilling test are executed on it. The result of that has confirmed the difficulties of cutting process on it as expectation. But the fact was also found that if the existing structure of the robot would be improved through the some method reinforcing the stiffness of it, a finish drilling process of surface will be able. This research will be continued in future, and if someone will study the more powerful stiffness reinforcement method which is applicable to existing multi articulated industrial robot, it will contribute a lot in the business rationalization of the enterprise through the low cost flexible drilling facilities and time saving of production system. And Several experimental results of geometry and its related error identification for an easy compensation/teaching methods on an industrial robot will also be included.