Research on Control Methods of Planar Motors based on the Modal Forces


There is tight electromagnetic and mechanical coupling among planar motor (PM) 6- degree of freedom (DOF) motions for photolithography in semiconductor manufacturing. For the purpose of achieving decoupled control of the 6-DOF motions, this paper presents the current-controlled model of linear motor (LM) as the actuators, the concept of the actuator forces and the modal forces, and the decoupled dynamics model based on the modal forces. Under some reasonable assumptions on the prototype motor kinematics and structure parameters, the modal forces method successfully decouples the 6-DOF dynamics models and all the dynamics models become simple 2nd order linear systems which can be controlled with multiform linear controller. For the prototype motor, the transformation matrices between the modal forces and the actuator forces are derived and the current-controlled block diagram is presented.

Meeting Name

2008 World Automation Congress, WAC 2008 (2008: Sept. 28 - Oct. 2, Waikoloa, HI)


Electrical and Computer Engineering

Keywords and Phrases

Block Diagrams; Control Methods; Controlled Model; Decoupled Control; Degree of Freedom (dof); Dynamics Models; Linear Controllers; Mechanical Coupling; Modal Forces; Planar Motors; Semiconductor Manufacturing; Structure Parameter; Transformation Matrices; Linear Control Systems; Actuators; Actuator Forces

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International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


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© 2008 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Oct 2008

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