Analytical and finite element simulation of a three-bar torsion spring

7th International Conference on Advanced Concepts in Mechanical Engineering

Rdoi, M.^1 ; Cicone, T.^2

Faculty of Transportation, University POLITEHNICA of Bucharest, Romania^1

Machine Elements and Tribology Department, University POLITEHNICA of Bucharest, Romania^2

关键词: 3-D finite elements;    3D finite-element simulation;    Analytical and numerical solutions;    Autonomous Vehicles;    Closed form solutions;    Parametric -analysis;    Static characteristic;    Torsion Springs;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/147/1/012008/pdf
DOI  :  10.1088/1757-899X/147/1/012008

来源: IOP

【 摘 要 】

The present study is dedicated to the innovative 3-bar torsion spring used as suspension solution for the first time at Lunokhod-1, the first autonomous vehicle sent for the exploration of the Moon in the early 70-ies by the former USSR. The paper describes a simple analytical model for calculation of spring static characteristics, taking into account both torsion and bending effects. Closed form solutions of this model allows quick and elegant parametric analysis. A comparison with a single torsion bar with the same stiffness reveal an increase of the maximum stress with more than 50%. A 3D finite element (FE) simulation is proposed to evaluate the accuracy of the analytical model. The model was meshed in an automated pattern (sweep for hubs and tetrahedrons for bars) with mesh morphing. Very close results between analytical and numerical solutions have been found, concluding that the analytical model is accurate. The 3-D finite element simulation was used to evaluate the effects of design details like fillet radius of the bars or contact stresses in the hex hub.