VEHICLE SUSPENSION AND STRUCTURE BORNE ROAD NOISE TESTING ON A 6-DOF, HIGH FREQUENCY SHAKER TABLE: FIRST OUTLINES

摘要

A CUBETM High Frequency 6-DOF Shaker Table has recently been installed at the KULeuven Noise and Vibration Laboratory. This paper describes two applications: multivariable controllers for vehicle suspension testing and structure borne road noise testing, from experiment design to first results. A first part is focused on the CUBETM High Frequency 6-DOF Shaker Table. This device features promising NVH testing performance and accuracy. Such a shaker table has recently been installed at the KULeuven Noise and Vibration Laboratory and the present work is part of an extensive test and benchmarking program. In this first section the layout of the lab, designed around the shaker and adapted to make the installation as clean, performing and versatile as possible, is discussed. A first application, within scope from the lab design phase, concerns non-linear MDOF vehicle suspension testing. With a dynamic range from 0 to 250 Hz and coherent response in all 6 DOFs, this facility allows characterization of vehicle suspensions, with respect to both the quasi-static and dynamic cross-axis relationships. In addition to this state of the art shaker, a contactless high accuracy 6-DOF Krypton K600 displacement measuring system is used, with up to four independent bodies monitored in the frequency range of interest. Classic acceleration and 6-DOF input force measurements complete the test setup. Two current research topics are presented in this paper, based on the use of the described test setup. The first research topic concerns advanced control techniques for MDOF test rigs. Three methods: decentralized, full-MIMO and inverse-based control, are discussed and compared for a bi-axial suspension test. The second research topic concerns structure borne road noise testing. In order to investigate the Road Noise behavior, MDOF road excitations are recorded on a testtrack. These signals are then used as target signals for the excitation on the shaker table. TWR software is used to accurately reproduce the target signals. Road measurements and test results from a 3-DOF road reproduction experiment are discussed.