A Combined Experimental and Analytical Procedure for Improving Automotive System Dynamics

Powerful capabilities for use in the analysis of complex automotive systems have recently been developed. These capabilities bring the newly developed electronic testing equipment together with the powerful computational techniques to perform a total system dynamic design analysis. The analysis tool developed is called the building block approach, whereby complex system behavior is defined by analyzing and combining the dynamic behavior of simpler components and subassemblies. The dynamic behavior of each component is obtained from a separate analytical investigation or from a specific type of experimental test procedure. Component data are then combined mathematically to predict dynamic behavior of the full system under the prescribed loading conditions. With the system simulation completed, design changes in any or all components can be evaluated. The effect of changes in any component on the operating behavior, vibration, noise, and stress can be ascertained. This paper describes the basic dynamic design analysis techniques which are available, and the automated testing methods and computer programs necessary to make the approach practical and successful. To demonstrate the application of this approach to automotive systems, the dynamic simulation of a heavy truck frame, cab, and cab mount system is described.