Proceedings of the
9th International Conference of Asian Society for Precision Engineering and Nanotechnology (ASPEN2022)
15 – 18 November 2022, Singapore
doi:10.3850/978-981-18-6021-8_OR-16-0312

An Impact-based Automatic Centering Actuator System for Ultra-Precision Turning

Seung-Kook Ro1,a, Gyungho Khim1 and Doo-Sun Choi2

1Department of Ultra-Precision Machines and Systems, Korea Institute of Machinery and Materials, 156 Gajeongbuk-no Yuseong-gu Daejeon, 34103, Korea

2Department of Nano-manufacturing Technology, Korea Institute of Machinery and Materials, 156 Gajeongbuk-no Yuseong-gu Daejeon, 34103, Korea

ABSTRACT

In this paper, we introduces an automatic workpiece centering system using an impact actuator for future use of automating centering process which is currently done bv time-consuming manual process. We were aimed to develop an actuator and automatic process to align workpiece center within 20 seconds. An impact actuator was designed to generate force to move work small displacement by continuously impacting during rotation. The proposed impact actuator has a voice coil motor for generating movements of two masses which are guided by miniature guides, and mass with smaller weight contacts workpiece. The measured eccentricity by a displacement was estimated on-line through LMS tracking method, and magnitude of excitation was calculated based on the tracked eccentricity. The proposed actuator was manufactured and integrated with a control system using low-cost micro-processor. The automatic centering actuator system was applied to a diamond turning machine for a micro lens core mold with continuous rotating speed of 60 rpm and 20 Hz of excitation frequency. It was demonstrated experimentally that centering workpiece was possible within 1 µm and no more than 20 seconds.

Keywords: Automatic centering, Impact actuator, Ultra-precision turning, LMS algorithm, Lens core mold



PDF Download