Measurement of Steering Gear impedance
J.D Varin
(submitted 4 April 2002;in revised form 11 May 2002)
ABSTRACT--Proper simulation of noise in hydraulic circuits requires reliable experimental data to be used in the simulations. In automotive power steering applications, obtaining reliable impedance data for both the pump and steering gear is critical for the success of any fluid-borne noise simulation program. Collecting data for power steering pumps has been the subject of various studies. steering gears, on the other hand, have received little attention. The purpose of this paper is to present a comprehensive assessment of the need of such data and describe a test setup for obtaining the data according to recent ISO standards. This paper describes the results obtained and presents several studies. In particular, the effects of pressure, steering position, slave pump and steering fluid on rack impedance will be studied. Furthermore, repeatability and production variability of measured data will be addressed.
