AUTHORS: Khairul Jauhari
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ABSTRACT: This paper presents a vibration reduction model of the radial vibration in a high precision spindle caused by unbalance force. The spindle-bearing system is considered as a flexible rotor supported by two sets of angular contact ball bearings. The finite element method (FEM) has been adopted for obtaining the spindlebearing system equation of motion. In this study, natural frequencies, critical frequencies and amplitude of the unbalance response caused by residual unbalance are determined in order to investigate the spindle-bearing system behavior. In this paper, we proposed a new combination stochastic algorithm model such as hybrid genetic algorithm (HGA) for minimizing radial vibration of the spindle-bearing system by raising the critical frequencies and reducing the amplitude of unbalance response, which considers shaft diameter, dynamic characteristic of the bearing, critical frequencies, and amplitude of the unbalance response, and computes optimum spindle diameter and the values of damping and stiffness of the bearing. In numerical simulation results show that by optimizing shaft diameter, and the values of damping and stiffness of the bearing, the spindle vibration amplitude at operating speed can be minimized. A spindle-bearing system about 4.25 µm radial vibration amplitude can be reduced with 2.33 µm accuracy
KEYWORDS: Flexible rotor, high precision spindle, optimization model, radial vibration amplitude, spindlebearing system
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