A stable interval observer for fault detection in the context of verified model-based design

The design of exponentially stable interval observers is often subject to assumptions related to monotone influences in the vector field. This may lead to significant restrictions, especially when the response of systems exhibiting an oscillatory behavior should be over-approximated under uncertain inputs. In order to overcome this issue, a stable interval observer for LTI systems with bounded inputs is proposed. It mainly relies on the assumption that the initial system is stable with no multiple poles. Any real or complex stable pole is authorized. The resulting exponentially stable interval observer is then applied to the detection of inconsistencies for the verified design of a vehicle suspension.