Multibody Dynamic Simulation of Steering Gear Systems With Three-Dimensional Surface Contacts

In an effort to understand steering systems performance and properties at the microscopic level, we developed Multibody simulations that include multiple three-dimensional gear surfaces that are in a dynamic state of contact and separation. These validated simulations capture the dynamics of high-speed impact of gears traveling small distances of 50 microns in less than 10 milliseconds. We exploited newly developed analytic, numeric, and computer tools to gain insight into steering gear forces, specifically, the mechanism behind the inception of mechanical knock in steering gear. The results provided a three dimensional geometric view of the sequence of events, in terms of gear surfaces in motion, their sudden contact, and subsequent force generation that lead to steering gear mechanical knock.

First we briefly present results that show the sequence of events that lead to knock. A brief discussion of the state of knowledge in Multibody system with three-dimensional surface contacts is used here to illustrate the limitations of such formulation on dynamic modeling of surfaces in three-dimensional high speed motions. Finally we discuss the methodology comprised of hardware, software, and analysis methods that are necessary for overcoming these limitations.