Marco Lovera

Bio: Marco Lovera is an academic researcher from Polytechnic University of Milan. The author has contributed to research in topics: Attitude control & System identification. The author has an hindex of 30, co-authored 249 publications receiving 3900 citations.

Periodic attitude control techniques for small satellites with magnetic actuators

Abstract: The problems of attitude stabilization and disturbance torque attenuation for a small spacecraft using magnetic actuators is considered and a solution to the problem in terms of optimal periodic control is proposed, based on an optimal estimation and compensation scheme for external disturbances for linear time-periodic systems.

Closed-loop subspace identification methods: an overview

Abstract: In this study, the authors present an overview of closed-loop subspace identification methods found in the recent literature Since a significant number of algorithms has appeared over the last decade, the authors highlight some of the key algorithms that can be shown to have a common origin in autoregressive modelling Many of the algorithms found in the literature are variants on the algorithms that are discussed here In this study, the aim is to give a clear overview of some of the more successful methods presented throughout the last decade Furthermore, the authors retrace these methods to a common origin and show how they differ The methods are compared both on the basis of simulation examples and real data Although the main focus in the literature has been on the identification of discrete-time models, identification of continuous-time models is also of practical interest Hence, the authors also provide an overview of the continuous-time formulation of the identification framework

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Attitude stabilization of rigid spacecraft with finite‐time convergence

Abstract: The problem of attitude control for a spacecraft model which is nonlinear in dynamics with inertia uncertainty and external disturbance is investigated in this paper. Two sliding mode controllers are proposed to force the state variables of the closed-loop system to converge to the origin in finite time. Specially, the second control design consists of the estimation of the uncertainty and disturbance by adaptive method and thus it achieves the decrease of undesired chattering effectively. Also, simulation results are presented to illustrate the effectiveness of the control strategies. Copyright © 2010 John Wiley & Sons, Ltd.

Impacts of impervious surface on watershed hydrology: A review

Abstract: Increased impervious surface area is a consequence of urbanization, with correspondent and significant effects on the hydrologic cycle. It is intuitive that an increased proportion of impervious surface brings with it shorter lag times between onset of precipitation and subsequently higher runoff peaks and total volume of runoff in receiving waters. Yet, documentation on quantitative relationships between the extent and type of impervious area and these hydrologic factors remains dispersed across several disciplines. We present a literature review on this subject to better understand and synthesize distinctions among different types of impermeable surface and their relative impacts, and describe the manner in which these surfaces are assessed for their putative impacts on landscape hydrology.

Subspace model identification-Part 1. The output-error state-space model identification class of algorithms

Abstract: In this paper, we present two novel algorithms to realize a finite dimensional, linear time-invariant state-space model from input-output data. The algorithms have a number of common features. They are classified as one of the subspace model identification schemes, in that a major part of the identification problem consists of calculating specially structured subspaces of spaces defined by the input-output data. This structure is then exploited in the calculation of a realization. Another common feature is their algorithmic organization: an RQ factorization followed by a singular value decomposition and the solution of an overdetermined set (or sets) of equations. The schemes assume that the underlying system has an output-error structure and that a measurable input sequence is available. The latter characteristic indicates that both schemes are versions of the MIMO Output-Error State Space model identification (MOESP) approach. The first algorithm is denoted in particular as the (elementary MOESP scheme)...

Modelling and Control of Robot Manipulators

Abstract: Feel lonely? What about reading books? Book is one of the greatest friends to accompany while in your lonely time. When you have no friends and activities somewhere and sometimes, reading book can be a great choice. This is not only for spending the time, it will increase the knowledge. Of course the b=benefits to take will relate to what kind of book that you are reading. And now, we will concern you to try reading modelling and control of robot manipulators as one of the reading material to finish quickly.