Lightweight Design Method for Micromanufacturing Systems Based on Multi-Objective Optimization

Area of Science:

• Mechanical Engineering
• Manufacturing Technology
• Computational Design

Background:

• Micromanufacturing systems require high precision and stiffness.
• Lightweighting is crucial for energy efficiency and dynamic performance.
• Existing designs often lack optimal structural integrity and mass distribution.

Purpose of the Study:

• To develop and validate a multi-stage collaborative design framework for synergistic lightweighting and performance enhancement.
• To optimize the structural design of ultra-precision Computer Numerical Control (CNC) machine tools.
• To significantly reduce machine tool weight while improving static and dynamic stiffness.

Main Methods:

• Sensitivity analysis to identify critical components (base, column, spindle box).
• Response Surface Methodology (RSM) to model mass and stress of the spindle box.
• Multi-objective optimization using a genetic clustering algorithm and variable-density topology optimization (SIMP model).

Main Results:

• Spindle box weight reduced by 57.2% (590 kg) under stress constraints (<45 MPa).
• Base and column weights reduced by 38.5% (2844 kg) and 41.5% (1292 kg) respectively.
• Maximum static deformation decreased by 47%, maximum stress by 40%, and natural frequency increased by 66% (to 84.08 Hz).

Conclusions:

• The proposed framework effectively achieves significant lightweighting (>3000 kg) and enhances static/dynamic performance.
• Optimized designs demonstrate improved stiffness and reduced deformation, crucial for high-end micromanufacturing.
• This approach offers a viable engineering pathway for advanced structural design in precision manufacturing systems.