Application Of Dynamic Correlation Technique And Model Updating On Truck Chassis

Abstract

Truck chassis is a major component in a vehicle system. It is often identified for refinement in order to develop vehicles with reduced cost and weight. Nowadays the process of chassis design in the automotive industry has been significantly refined with the high capabilities of advanced computer aided design and engineering tools,. The application of FEA such as structural modification and optimization is used to reduce component complexity, weight and subsequently cost. Because the level of model complexity can be high, the opportunity for error can also be high. For this reason, some form of model verification is needed before design decisions made in the FEA environment can be implemented in production. This paper looks into the application of dynamic correlation techniques for verification of the FEA models of truck chassis. The dynamic characteristics of truck chassis such as the natural frequency and mode shape were determined using finite element method. Experimental modal analysis was carried out to validate the FE models. Initial results from both analysis show that the truck chassis experienced 1st torsion mode for 1st natural frequency, 1st bending mode for 2nd natural frequency, 2nd torsion mode for 3rd natural frequency and 2nd bending mode for 4th natural frequency. However there is a small discrepancy in terms of frequency. Thus, the model updating of truck chassis model was done by adjusting the selective properties such as Modulus Young and Poisson ratio in order to get better agreement in the natural frequency between both analysis. Finally, the modifications of the updated FE truck chassis model was suggested such as by considering adding the stiffener. The purpose is to reduce the vibration as well as to improve the strength of the truck chassis.