A New Kinematic Model for the Closure Equations of the Generalized Stewart Platform Mechanism

  • C. Innocenti
  • V. Parenti-Castelli
Conference paper


The paper deals with the direct position analysis of the six degrees of freedom parallel manipulator known as generalized Stewart Platform Mechanism. When a set of actuator displacements is given the mechanism becomes a statically determined structure and the analysis solves for the closure of the structure. The governing equations are nonlinear and many solutions are possible. Kinematic models reported in the literature bring to systems of six equations in six unknowns which are solved numerically because of their complexity. Based on a novel approach a new kinematic model of the structure is presented in this paper. It leads to a system of three equations in three unknowns that greatly reduces the computational burden. Finally a case study has been reported.


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Copyright information

© Springer-Verlag Wien 1991

Authors and Affiliations

  • C. Innocenti
    • 1
  • V. Parenti-Castelli
    • 1
  1. 1.Dipartimento di Ingegneria delle costruzioni meccaniche nucleari, aeronautiche edi MetallurgiaUniversità di BolognaBolognaItaly

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