Preview Control Barrier Functions for Linear Continuous-Time Systems with Previewable Disturbances

Many (semi-)autonomous systems are equipped with mechanisms that provide a window of projecting into the future. Predictions/projections of future exogenous inputs or disturbances, commonly referred to as preview or lookahead, have been widely studied in predictive control systems to yield less conservative controllers that would otherwise have to consider them as worst-case disturbances. However, the incorporation of such preview information has been less studied in the context of safety. Thus, this paper proposes a preview control barrier function (Prev-CBF) that can enforce the controlled invariance of a safe set for a class of linear continuous-time systems with previewable disturbances. Specifically, our approach can leverage future information about external disturbances, e.g., road gradients or predictive trajectories of other agents/vehicles, for a (small) window into the future and can explicitly take input constraints/bounds into consideration to provide strong safety guarantees in a less conservative manner than existing approaches that do not leverage such information.