Stiffness Analysis Of Multi-Chain Parallel Robotic Systems

TL;DR

This paper introduces a novel stiffness modeling method for multi-chain parallel robots that uses FEA-based link evaluation and a new solution approach to analyze stiffness, including singular postures and internal forces.

Contribution

It presents a new FEA-based stiffness modeling technique with a unique solution strategy for kinetostatic equations, enabling analysis of singular postures and internal forces.

Findings

Validated on Orthoglide manipulator examples

Able to compute stiffness matrices for singular configurations

Accounts for internal force effects in stiffness analysis

Abstract

The paper presents a new stiffness modelling method for multi-chain parallel robotic manipulators with flexible links and compliant actuating joints. In contrast to other works, the method involves a FEA-based link stiffness evaluation and employs a new solution strategy of the kinetostatic equations, which allows computing the stiffness matrix for singular postures and to take into account influence of the internal forces. The advantages of the developed technique are confirmed by application examples, which deal with stiffness analysis of the Orthoglide manipulator.