US Patent 7558661 Adaptive maneuver based diagnostics for vehicle dynamics

A vehicle stability control system diagnostic strategy, wherein the diagnostic strategy may be adaptively applied based upon the identified maneuver states of the vehicle. The diagnostic architecture contains three vehicle state observers (i.e., models) each based on inputs from only two of the three sensors (yaw rate, lateral acceleration, and hand wheel angle). More particularly, the first observer does not consider lateral acceleration input. The second observer does not consider yaw rate sensor input and the third does not consider hand wheel angle (UWA) sensor input in determining the vehicle state. However, estimated vehicle speed input is used by all the observers. For example, the first observer detects a maneuver state based on yaw rate and HWA and vehicle speed inputs. Then it diagnoses the lateral acceleration sensor failure based on the observer output.