A Novel Geometric Modeling and Calculation Method for Forward Displacement Analysis of 6-3 Stewart Platforms

A novel geometric modeling and calculation method for forward displacement analysis of the 6-3 Stewart platforms is proposed by using the conformal geometric algebra (CGA) framework. Firstly, two formulas between 2-blade and 1-blade are formulated. Secondly, the expressions for two spherical joints of the moving platform are given via CGA operation. Thirdly, a coordinate-invariant geometric constraint equation is deduced. Fourthly, a 16-degree univariate polynomial equation without algebraic elimination by using the Euler angle substitution is presented. Fifthly, the coordinates of three spherical joints on the moving platform are calculated without judging the radical symbols. Finally, two numerical examples are used to verify the method. The highlight of this paper is that a new geometric modeling and calculation method without algebraic elimination is obtained by using the determinant form of the CGA inner product algorithm, which provides a new idea to solve a more complex spatial parallel mechanism in the future.

A Systematic Literature Review for Multimedia Learning Objects Applied to Stewart Platforms Using Software Engineering Methods

This article describes a systematic literature review (SLR), a methodology to be used in the survey of articles, monographs, dissertations and theses, in scientific databases, to provide a reference bibliography for the construction of multimedia learning objects applied to Stewart platforms, using Software Engineering methods. The bases existent in the literature between the years of 2009 and 2012 were analyzed. The methodology used was based on the adaptation of a revision protocol that suggests for a good SLR, to follow some steps, being: planning, primary reading, formulation of questions for checking if the work fits the subject and classification. The use of SLR assisted in the bibliographic survey process bringing successful results and relevant publications with high impact factors, thus making a solid basis for several works in the research fields.