Computation Time Efficient Stiffness Analysis of the Modified R-CUBE Mechanism

  • İ. GörgülüEmail author
  • M. İ. C. Dede
Conference paper
Part of the Mechanisms and Machine Science book series (Mechan. Machine Science, volume 68)


Parallel manipulators are known to be more stiff than the serial manipulators. However, modeling the stiffness for parallel manipulators are difficult compared to serial manipulators due to the constrained structure and passive joints. In addition, computation of the stiffness model for parallel manipulators are exhausting since it requires an iterative solution algorithm due requirement of force-position convergence of all serial chains connecting to the same mobile platform. Direct solutions are faster however, they lack in accuracy. In this study, direct solution is preferred for real-time application and analytic stiffness model of the modified R-CUBE mechanism is obtained by using Virtual Joint Method (VJM). The finite element (FE) model is constructed and simulated to validate the analytical model. Then, a combination of external wrenches \(\pm 5\) N in various directions are applied on the mobile platform in both FE and VJM in some critical poses. Finally, the computed numerical results are listed and compared along with their computation times.


Stiffness Parallel manipulator Virtual joint method Finite element analysis 



This work is supported in part by The Scientific and Technological Research Council of Turkey via grant number 117M405.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Izmir Institute of TechnologyIzmirTurkey

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