The notion of observability and detectability for a particular class of hybrid systems, linear continuous-time switching systems, is investigated. We compare some of the definitions of observability previously offered and we analyze their drawbacks. A novel definition of observability is proposed corresponding to the possibility of reconstructing the state of the system from the knowledge of th...

For a quantum Hamiltonian H = H(λ), the observability of the energies E may be robust (whenever all E are real at all λ) or, otherwise, conditional. Using a pseudoHermitian family of N−state chain models H = H(λ) we discuss some generic properties of conditionally observable spectra.

Limited observability is the assumption that economic agents can only observe a finite amount of information. Given this constraint, contracts among agents are necessarily finite and incomplete in comparison to the ideal complete contract that we model as infinite in detail. We consider the extent that finite contracts can approximate the idealized complete contracts. The objectives of the pape...

In this paper, we study estimator inconsistency in Vision-aided Inertial Navigation Systems (VINS). We show that standard (linearized) estimation approaches, such as the Extended Kalman Filter (EKF), can fundamentally alter the system observability properties, in terms of the number and structure of the unobservable directions. This in turn allows the influx of spurious information, leading to ...

Abstract. We analyze controllability and observability conditions for second order descriptor systems and show how the classical conditions for first order systems can be generalized to this case. We show that performing a classical transformation to first order form may destroy some controllability and observability properties. As an example, we demonstrate that the loss of impulse controllabi...

This paper is concerned with path planning for under-sensed vehicles, where the vehicle has insufficient sensors to estimate its state without active control. One such system is an autonomous underwater vehicle, which typically does not have complete inertial position information. Using the condition number of the observability gramian as a cost functional, we develop an observability optimal c...

In this paper, we deal with the observability problem of a class of Hybrid Systems whose output is a timed string on a finite alphabet. We determine under which conditions it is always possible to immediately detect, using the observed output, when the system enters a given discrete state. We illustrate how to construct a Timed Automaton that is an abstraction of the given Hybrid System, and th...

We analyze the problem of boundary observability of the finite-difference space semi-discretizations of the 2-d wave equation in the square. We prove the uniform (with respect to the mesh size) boundary observability for the solutions obtained by the two-grid preconditioner introduced by Glowinski [6]. Our method uses previously known uniform observability inequalities for low frequency solutio...

In this paper, we deal with the genericity of the observability property and the existence of asymptotic observers for nonlinear systems. In the case where the number of outputs is larger than the number of inputs and the state space is compact, we prove that observability in a very strong sense (more or less, observability for each sufficiently differentiable input) is generic. This is obtaine...

By analogy to the development for dynamic systems, concepts of observability and redundancy may be developed with respect to a steady state system. These concepts differ from their counterparts for dynamic systems in that they can be used to characterize individual variables and local behavior as well as system and global behavior. Relations between local observability, global observability, ca...