Precision Machining by Local Machining Station Method

Research Project

Project/Area Number	07650155
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	機械工作・生産工学
Research Institution	Toyota Technological Institute
Principal Investigator	FURUTANI Katsushi Toyta Technological Institute, School of Engineering, Lecturer, 大学院・工学研究科, 講師 (00238685)
Co-Investigator(Kenkyū-buntansha)	MOHRI Naotake Toyota Technological Institute, School of Engineering, Professor, 大学院・工学研究科, 教授 (90126186)
Project Period (FY)	1995 – 1996
Project Status	Completed (Fiscal Year 1996)
Budget Amount *help	¥2,800,000 (Direct Cost: ¥2,800,000) Fiscal Year 1996: ¥1,600,000 (Direct Cost: ¥1,600,000) Fiscal Year 1995: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	precision machining / end effector / electrical discharge machining / robot / positioning / parallel mechanism / パラレルメカニズム
Research Abstract	In this study, Local Machining Station (LMS) method is proposed for automatic machining systems with industrial robots. This method aims to improve the positioning accuracy for a local area of a large workpiece and the stiffness of the robot machining system. The LMS consists of a reference plate with displacement senosors, several legs and a movable small machine tool. The length of the legs is variable. The lags and the machine tool are fixed on the reference plate. The LMS is mounted on a robot arm as an end-effector. When the LMS is clamped onto a large workpiece with its legs, the stiffness of the robot machining system increases. Since the position of the movable machine tool is measured with the displacement sensors on the reference plate, the positioning accuracy for a local area of the large workpiece becomes higher. A prototype of LMS is manufactured in trial. A pencil-size electrical discharge machine is installed on the reference plate as the movable machine tool. The prototype is positioned by the PI control. The length of the legs is measured with potentiometers. The positioning accuracy of the prototype is several tens micrometer order. A coordinate system is settled by using holes on a workpiece and some other holes are machined on the coordinate system. The accuracy of machined holes by the LMS method is better than that with a robot.