Use of Fuzzy Logic in Wheel Slip Assignment - Part II: Yaw Rate Control with Sideslip Angle Limitation 2002-01-1220
This paper is an extension to the work presented in part I . The control objective is still the same - use a logic based control design technique to assign a wheel slip, λ, to each corner of a vehicle, to track overall desired vehicle dynamics. As in part I, a fuzzy logic based controller is the primary control, with additional logic to select the inside/outside classifiers for the wheels. In part I, only the reduction of yaw rate error, e, was considered. It was shown that, although the overall system had satisfactory performance, there was slight deteriorization in the tracking performance when trying to compensate through a significant vehicle sideslip angle, β. In this paper, additional logic is introduced into the control to limit the vehicle sideslip angle, β; thus, allowing for a more robust desired yaw rate, Ωd, tracking control performance. The emergency lane change maneuver is simulated to show the effectiveness of the redesigned control. An analysis is performed between the control that includes limiting the vehicle sideslip angle, β, and the control that does not limit the vehicle sideslip angle, β (from part I). This analysis shows how some of the tire force characteristics differ, while still being able to allow the system to track the desired yaw rate, Ωd.