Parametric Stiffness Analysis of the Orthoglide

TL;DR

This paper develops a symbolic, parametric stiffness analysis method for the Orthoglide, enabling the study of how design parameters influence stiffness and static displacements during machining operations.

Contribution

It introduces a symbolic computation approach for stiffness analysis of parallel manipulators, allowing parametric studies of design impacts on stiffness and displacements.

Findings

Identified critical links affecting stiffness.

Modeled static displacements during slot milling.

Demonstrated applicability to various machining operations.

Abstract

This paper presents a parametric stiffness analysis of the Orthoglide, a 3-DOF translational Parallel Kinematic Machine. First, a compliant modeling of the Orthoglide is conducted based on an existing method. Then stiffness matrix is symbolically computed. This allows one to easily study the influence of the geometric design parameters on the matrix elements. Critical links are displayed. Cutting forces are then modeled so that static displacements of the Orthoglide tool during slot milling are symbolically computed. Influence of the geometric design parameters on the static displacements is checked as well. Other machining operations can be modeled. This parametric stiffness analysis can be applied to any parallel manipulator for which stiffness is a critical issue.