Shape optimization, model updating and empirical modeling applied to the design synthesis of a heavy truck side guard

This work describes the use of different optimization approaches aiming at the automatic design synthesis of a heavy truck side guard (bumper). At a preliminary stage, an existing version of the side guard undergoes a geometrical simplification in order to improve manufacturability and assemblability aspects of the design. This geometrical simplification is achieved through a fully automatic shape optimization procedure, taking into account that key mechanical features of the original configuration are to be kept in the simplified design. In the sequence, the numerical model of the simplified version of the bumper is updated to match the experimental results obtained through modal testing of a prototype in laboratory conditions. For comparison purposes, two automatic optimization techniques are used in the modal matching procedure. After achieving the desired configuration changes (by means of shape optimization) and a reliable model representing the system’s behaviour (by means of the modal matching procedure), the design of the heavy truck side bumper is improved, again by using an automatic approach based on numerical optimization techniques. The purpose of this optimization procedure is to tune the natural vibrating frequencies of the side bumper so that its behaviour with respect to noise, vibration and harshness reaches predefined performance levels. Aiming at future design improvement, to be held in a multidisciplinary context that accounts for crashworthiness issues, empirical models (nonlinear response surfaces) are developed for the implementation of such optimization procedure. Finally, the general conclusions and perspectives for future research work are presented, stressing at the usefulness of numerical optimization techniques in supporting the automation of an entire design procedure, from conceptual definition to multidisciplinary performance improvement.