Development of a Software Tool for the Optimal Design of Mount Systems Based on Detailed Finite Element Models of Vehicle Sub-structures

Optimal Mount System Design Based on
Detailed Finite Element Models of Vehicle Sub-structures

This body mount system is utilized for isolating dynamic load and vibration of the cab from the rest of vehicle system. The behavior of the mount system not only depends on the performance of individual mounts but also on the complete system configuration. A systematic approach is proposed for optimal design of the truck body mount system. Design variables include the mount locations and mechanical properties of each individual mount. First, an advanced component mode-based substructuring method is utilized for developing reduced-order models of the cab body and the other related subsystems, such as the chassis frame, from the original detailed finite element models. An optimization procedure is then developed which can be used to determine the geometric distribution of the mounts and their mechanical characteristics (e.g., dynamic stiffness and damping) for minimizing vibration amplitudes at the given locations in the body structure over a frequency range of interest.

To determine the optimal mount distribution, a path variable is introduced at the interface of cab and frame, which allows placing of each individual mount along the chassis frame in the permitted range. The optimal mount location design problem is thus transformed to an equivalent problem that determines the optimal path variables of each mount. MATLAB code is developed for the mount system design problem. An example mount system design was developed to illustrate the effectiveness and efficiency of the proposed approach, in which the mount stiffness and the mount locations are optimized simultaneously. The developed optimization tool can be extended for optimizing other general mounting systems, such as an engine mount system.