Determination of Constant Orientation Workspace of a Stewart Platform by Geometrical Method

Abstract:

Determination of workspace is one of the main considerations in the design of any robot since the workspace geometry is considered a fundamental issue for robot design. This also plays a crucial role in trajectory planning. Among parallel manipulators, 6-DOF Stewart platforms is the most researched and widely used robot. However, till date there is no closed form expression of workspace volume for Stewart platform. In this paper, a novel method is proposed to find out the workspace volume of Stewart platform. In this paper, individual workspace of each leg of the manipulator (P-U-S) is determined and then translated by a common distance towards their geometrical center thus generating constant orientation workspace. To determine the workspace volume, geometric intersection of the six spheres is computed. This results in workspace of definite shape and size, whose volume is calculated using simple formulae. It is observed that the geometric way of determination of workspace area is computationally less tedious than the algebraic method. This also helps a lot for workspace optimization of such manipulators.

• Periodical: Applied Mechanics and Materials (Volumes 813-814)
• Pages: 997-1001
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.813-814.997
• Online since: November 2015
• Authors: S. Gokul Narasimhan, R. Shrivatsan, K. Venkatasubramanian, Anjan Kumar Dash*
• Keywords: Geometrical Method, Stewart Platform, Workspace Determination, Workspace Volume

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