Assembly Adjustment Process Planning of Precision Machine Tools Based on Optimal Estimation of Variation Propagation

doi:10.3901/JME.2020.11.172

Abstract

Abstract: Precision machine tool is the base of modern equipment manufacturing industry. Geometric accuracy is the key requirement for machine tools. However, assembly process planning of machine tools mainly depends on the experience of designers. Adjustment process is usually repeated several times due to the lack of quantitative analysis and optimal planning. A method for assembly adjustment process planning of precision machine tools is proposed. Based on the state space model of assembly variation propagation of machine tools, Kalman filter is used to estimate the variation accumulation in each assembly step. Optimal control is introduced to obtain the optimal adjustment process to meet the final assembly accuracy based on estimation of the variation accumulation in the current step. Measurement uncertainty, assembly accuracy requirement and time cost of adjustment are taken into account in this method. The optimal adjustment process and the amount of adjustment can be calculated so that technicians only need to adjust one time to achieve the assembly accuracy. Finally, the feasibility and effectiveness of the proposed method are verified through the case study of a horizontal machining center assembly.

Key words: machine tool, assembly, adjustment process, optimal estimation, optimal control

CLC Number:

TH161

GUO Junkang, LI Baotong, HONG Jun, LI Xinbo. Assembly Adjustment Process Planning of Precision Machine Tools Based on Optimal Estimation of Variation Propagation[J]. Journal of Mechanical Engineering, 2020, 56(11): 172-180.

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