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This paper considers nonlinear systems with full state feedback, a central controller and distributed sensors not co-located with the central controller. We present a methodology for designing decentralized asynchronous event-triggers, which utilize only locally available information, for determining the time instants of transmission from the sensors to the central controller. The proposed design guarantees a positive lower bound for the inter-transmission times of each sensor, while ensuring asymptotic stability of the origin of the system with an arbitrary, but priorly fixed, compact region of attraction. In the special case of Linear Time Invariant (LTI) systems, global asymptotic stability is guaranteed and scale invariance of inter-transmission times is preserved. A modified design method is also proposed for nonlinear systems, with the addition of event-triggered communication from the controller to the sensors, that promises to significantly increase the average sensor inter-transmission times compared to the case where the controller does not transmit data to the sensors. The proposed designs are illustrated through simulations of a linear and a nonlinear example. [ABSTRACT FROM AUTHOR]

In this technical note, we study an event-based control algorithm for trajectory tracking in nonlinear systems. The desired trajectory is modelled as the solution of a reference system with an exogenous input and it is assumed that the desired trajectory and the exogenous input to the reference system are uniformly bounded. Given a continuous-time control law that guarantees global uniform asymptotic tracking of the desired trajectory, our algorithm provides an event-based controller that not only guarantees uniform ultimate boundedness of the tracking error, but also ensures non-accumulation of inter-execution times. In the case that the derivative of the exogenous input to the reference system is also uniformly bounded, an arbitrarily small ultimate bound can be designed. If the exogenous input to the reference system is piecewise continuous and not differentiable everywhere then the achievable ultimate bound is constrained and the result is local, though with a known region of attraction. The main ideas in the technical note are illustrated through simulations of trajectory tracking by a nonlinear system. [ABSTRACT FROM AUTHOR]

In this technical note, we study output synchronization of networked multiagent systems. The agents, modeled as nonlinear systems with relative degree one, exchange information over a network described by an interagent communication graph. Inspired by the results of Igarashi , we extend our earlier results on output synchronization to include the case of strongly connected graphs. We first demonstrate output synchronization for input-output passive systems communicating over strongly connected graphs and include the practical case of constant time delays in communication. It is well known (Byrnes ) that weakly minimum phase systems with relative degree one are feedback equivalent to a passive system with a positive definite storage function. We exploit this feedback equivalence to develop control laws for output synchronization of such systems, exchanging outputs on strongly connected graphs, and in the presence of communication delays. A numerical example is also presented to illustrate the proposed results. [ABSTRACT FROM AUTHOR]