Abstract
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 non-linear and many solutions are possible. Kinematic models reported in the literature relate 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.
Sommario
Il lavoro presenta l'analisi di posizione diretta del manipolatore parallelo a sei gradi di libertà noto come piattaforma di Stewart generalizzata. Fissate le variabili del moto delle coppie cinematiche attuate, l'analisi equivale alla ricerca delle configurazioni di chiusura di una struttura staticamente determinata. I modelli cinematici reperibili in letteratura riconducono il problema alla soluzione, affrontata con tecniche numeriche, di un sistema di sei equazioni non lineari in un corrispondente numero di incognite. Di contro, la metodologia proposta riduce l'analisi alla soluzione numerica di un sistema di tre equazioni non lineari in tre incognite, a diretto vantaggio dell'efficienza computazionale.
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Innocenti, C., Parenti-Castelli, V. A new kinematic model for the closure equations of the generalized Stewart platform mechanism. Meccanica 26, 247–252 (1992). https://doi.org/10.1007/BF00430941
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DOI: https://doi.org/10.1007/BF00430941