Development of a Lens Driving Maglev Actuator for Laser Beam Off-Axis Cutting and Deep Piercing

Abstract

In laser beam cutting and laser piercing process, the machining speed and quality are very sensitive to the flow of assist gas and laser beam focusing position. In order not only to improve the cutting speed and the removal capability of the molten material and to save the consumption of the gas flow in laser beam cutting, but also to realize high speed piercing of high aspect-ratio holes, a magnetic-levitated (maglev) lens driving actuator was proposed and fabricated. The actuator can drive the lens to achieve real-time positioning control of the relative radial displacement between the lens axis and the assist gas jet nozzle axis (off-axis control) in radial directions in a range of ±1mm within 1.5 μm of tracking error and bandwidths more than 150Hz, and to achieve real-time positioning control of laser beam focusing point in axial direction in a range of ±5mm within 3 μm of tracking error and bandwidth more than 100Hz.

Design and Analysis of 5-DOF Compact Electromagnetic Levitation Actuator for Lens Control of Laser Cutting Machine

“…Luan [18] and Zhang [19] designed a controllable magnetic levitation actuator for an EDM machine tool to improve the stability of the inter pole voltage, hence the machining speed increases to 3.925 µs. Dongjue He [20,21] designed a novel air core coil type electro-magnetic driving unit to actuate the lens holder, which can achieve a range of ±5 mm with a tracking error of less than 12 µm and a bandwidth of more than 100 Hz in the axial direction. However, the above magnetic levitation driver has a large volume, a large mover mass, and a large motion inertia, resulting in slow control accuracy and response speed.…”

Improvement in Position Response of Laser Focus Controlled Magnetic Actuator Based on Mixed Sensitivity Robust Control

“…Zhang X. et al designed a high-speed, high-precision electromagnetic actuator that can be connected with traditional laser cutting machine tools to control the relative position of the laser beam's axis and the auxiliary gas's axis [27]. He D. et al proposed a 6-DOF (degrees of freedom) magnetically levitated lens-driven actuator for off-axis laser cutting control [28,29]. M Y. et al investigated a 2-DOF electromagnetic actuator for laser off-axis cutting and achieved a positioning stroke of ±500 µm [30].…”

High Precision Magnetic Levitation Actuator for Micro-EDM

“…Kirill Poletkin [20] investigated the static pull-in of a tilt drive in a hybrid levitation micro-actuator and nonlinear modeling of the calculation of the mutual inductance and the action force between two circular filaments and experimentally verified the accuracy of the developed model, predicting the pull-in parameters of the hybrid levitation actuator with the developed analytical tool. Dongjue HE et al [21] designed a magnetic levitation lens driving actuator, which is applied in laser processing; the actuator drives the lens to achieve real-time positioning of the laser beam focus point with good control performance and positioning accuracy. Tong Zheng et al [22] designed a sizing optimization method to determine the magnetic levitation actuator for a rotary table and validated the effectiveness and accuracy of the method using simulation followed by experiments.…”