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Invited Paper Hybrid system theory lies at the intersection of the fields of engineering control theory and computer science verification. It is defined as the modeling, analysis, and control of systems that involve the interaction of both discrete state systems, represented by finite automata, and continuous state dynamics, represented by differential(More)
—Hybrid systems combine discrete state dynamics which model mode switching, with continuous state dynamics which model physical processes. Hybrid systems can be controlled by affecting both their discrete mode logic and continuous dynamics: in many systems, such as commercial aircraft, these can be controlled both automatically and using manual control. A(More)
We address systems which have multiple objectives: broadly speaking, these objectives can be thought of as safety and performance goals. Guaranteeing safety is our rst priority, satisfying performance criteria our second. In this paper, we compute the system's safe operating space and represent it in closed form, and then, within this space, we compute(More)
While a number of Lagrangian algorithms to approximate reachability in dozens or even hundreds of dimensions for systems with linear dynamics have recently appeared in the literature, no similarly scalable algorithms for approximating viable sets have been developed. In this paper we describe a connection between reachability and viability that enables us(More)
A method for the numerical computation of reachable sets for hybrid systems is presented and applied to the design and safety analysis of autoland systems. It is shown to be applicable to specific phases of landing: descent, flare, and touchdown. The method is based on optimal control and level set methods; it simultaneously computes a maximal controlled(More)
— A human interacting with a hybrid system is often presented, through information displays, with a simplified representation of the underlying system. This interface should not overwhelm the human with unnecessary information, and thus usually contains only a subset of information about the true system model, yet, if properly designed, represents an(More)
Modern commercial aircraft have extensive automation which helps the pilot by performing computations, obtaining data, and completing procedural tasks. The pilot display must contain enough information so that the pilot can correctly predict the aircraft's behavior, while not overloading the pilot with unnecessary information. Human-automation interaction(More)
Since its founding, NASA has been dedicated to the advancement of aeronautics and space science. The NASA Scientific and Technical Information (STI) Program Office plays a key part in helping NASA maintain this important role. The NASA STI Program Office is operated by Langley Research Center, the Lead Center for NASA's scientific and technical information.(More)
We present a connection between the viability kernel and maximal reachable sets. Current numerical schemes that compute the viability kernel suffer from a complexity that is exponential in the dimension of the state space. In contrast, extremely efficient and scalable techniques are available that compute maximal reachable sets. We show that under certain(More)