A Fast Forward Kinematic Analysis of Stewart Platform

스튜어트 플랫폼의 빠른 순기구학 해석

Ha, Hyeon-Pyo;Han, Myeong-Cheol

  • Published : 2001.03.01


The inverse kinematics problem of Stewart platform is straightforward, but no closed form solution of the forward kinematic problem has been presented. Since we need the real-time forward kinematic solution in MIMO control and the motion monitoring of the platform, it is important to acquire the 6 DOF displacements of the platform from measured lengths of six cylinders in small sampling period. Newton-Raphson method a simple algorithm and good convergence, but it takes too long calculation time. So we reduce 6 nonlinear kinematic equations to 3 polynomials using Nairs method and 3 polynomials to 2 polynomials. Then Newton-Raphson method is used to solve 3 polynomials and 2 polynomials respectively. We investigate operation counts and performance of three methods which come from the equation reduction and Newton-Raphson method, and choose the best method.


Stewart Platform;Forward Kinematics;Newton-Raphson Method


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