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UM E-Theses Collection (澳門大學電子學位論文庫)

Title

Design, modeling and control of a compliant parallel XY micro-motion stage with complete decoupling property

English Abstract

A novel compliant parallel XY micro-motion stage is proposed to fulfill positioning and manipulation with micro- or nanoscale precision. With a symmetric 4-PP structure, the XY stage has complete decoupling property. The stage is driven by piezoelectric actuators (PZT), and right-circular flexure hinge is adopted to convey the movement. Double four-bar flexure is chosen as the prismatic joint because of its better stiffness performance than double parallelogram flexure. The compliance model of the mechanism is built using simplified compliance matrix method, and then the kinematics, workspace and stress are analyzed. Lagrange’s equation is employed to derive the dynamic model of the mechanism. The dimensions are optimized using particle swarm optimization (PSO) algorithm in order to maximize the natural frequencies. Finite element analysis (FEA) result indicates that the XY stage with optimal dimensions has a linear force-deflection relationship and ideal decoupling property. The first-mode natural frequency is as high as 720.52 Hz, and the stage has the potential to achieve a 105 μm × 105 μm square workspace. To cope with the hysteresis existing in the PZT, the control system is constructed by a proportional-integral-derivative (PID) feedback controller with a feed-forward hysteresis compensator based on Preisach model. A prototype of the completely decoupled XY stage is fabricated with aluminum alloy AL7075-T6 using wire electric discharge machining (WEDM) technique. The static test shows that the XY stage has a 19.2 μm × 18.8 μm rectangular workspace with coupling less than 5%. The numerical Preisach model of hysteresis is built according to the experimental data, and the control strategy is implemented by a personal computer (PC) with MATLAB software. With the closed-loop control system, the XY stage can complete positioning, tracking and contouring tasks with small error.

Issue date

2011.

Author

Huang, Ji Ming

Faculty

Faculty of Science and Technology

Department

Department of Electromechanical Engineering

Degree

M.Sc.

Subject

Machinery, Kinematics of

Mechanical movements -- Design and construction

Supervisor

Li, Yang Min

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Location
1/F Zone C
Library URL
991007337229706306