A semi-analytical approach for computing the largest singularity-free spheres of a class of 6-6 Stewart-Gough platforms for specified orientation workspaces

TL;DR

This paper introduces a semi-analytical method to compute the largest singularity-free spheres for 6-6 Stewart-Gough platforms within specified orientation workspaces, aiding in analysis and design.

Contribution

It presents a novel semi-analytical approach for calculating the largest singularity-free spheres of SGPMs over orientation workspaces, with numerical validation on different architectures.

Findings

The method effectively computes SFS volumes for various SGPM architectures.

Numerical experiments compare the performance of different platform designs.

The approach offers insights for optimizing SGPM design and workspace analysis.

Abstract

This article presents a method for computing the largest singularity-free sphere (SFS) of a 6-6 Stewart-Gough platform manipulator (SGPM) over a specified orientation workspace. For a fixed orientation of the moving platform, the SFS is computed analytically. This process is repeated over a set of samples generated within the orientation workspace, and the smallest among them is designated as the desired SFS for the given orientation workspace. Numerical experiments are performed on four distinct architectures of the SGPM to understand their relative performances w.r.t. SFS volumes over the same orientation workspace. This study demonstrates the potential utility of the proposed computational method both in analysis and design of SGPMs.