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Finite Element Steering Wheel for Heavy Vehicles, Testing and Modeling

Anees Ur Rehman ; Mehdi Esmaeili Najafabadi
Göteborg : Chalmers tekniska högskola, 2011. Diploma work - Department of Applied Mechanics, Chalmers University of Technology, Göteborg, Sweden, ISSN 1652-8557; 2011:66, 2011.
[Examensarbete på avancerad nivå]

The main aim of this study was to validate an already existing Finite Element (FE) model of a truck steering wheel, using experimental testing and computer modeling. Statistics show a high risk of sustaining severe injuries, in a frontal crash of heavy vehicles, due to steering wheel rim to thorax contact. The Hybrid III crash test dummy is now also used for analyzing heavy vehicle frontal crashes. It was originally developed for passenger cars and load cases common to them. To use in heavy vehicles, loading pattern to Hybrid III torso is now changed from the central hub to the rim of steering wheel. The Hybrid III crash test dummy is also available in FE codes. In order to investigate the heavy vehicle crashes in FE, a validated FE steering wheel model is also required. An impact test setup was designed and replicated both in physical testing and computer modeling. Since the steering wheel can be adjusted at different tilt angles of the rim during driving, a set of tilt angles 0, 10, 20 and 30 degree was selected to see the behavior of steering wheel on impact with the rigid steel plate. The contact force, impact plate displacement and component deformations were the key parameters to be observed and compared, in order to validate the FE steering wheel model. During physical tests for all the tilt angles, the steering wheel showed a stiff behavior regarding force level and horizontal displacement of the impact plate. Variation in peak force level during simulation and physical tests is less than 5% for 0 and 10 degree. The simulation results were considered validated for 78 mm and 66 mm of impact plate displacement for 0 and 10 degree respectively. Similarly, peak force level was found 26% and 45% higher in physical tests for 20 and 30 degree respectively. The simulation results were found out of the corridor limits, and FE model was not considered as validated for 20 and 30 degree tilt angles. Presence of foam is found one of the major differences between the steering wheel and its FE model, as this foam absorbs some energy from the impact plate. This foam is absent in FE model. For a better agreement of FE model with the steering wheel, FE model may need to be stiffer. Modeling of foam around the steering wheel can be the other alternative.

Nyckelord: Heavy vehicle steering wheel, Frontal crash, Impact test-setup, Physical testing and simulations, Rim tilt angles, Contact force, Rim deformation, FE model validation.

Publikationen registrerades 2012-02-10. Den ändrades senast 2013-04-04

CPL ID: 155010

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