A LaSalle's Invariance Theory for a class of first-order evolution variational inequalities is developed. Using this approach, stability and asymptotic properties of important classes of second-order dynamic systems are studied. The theoretical results of the paper are supported by examples in nonsmooth Mechanics and some numerical simulations.
A method for backstepping control of rigid body motion is proposed. The control variables are torques and the force along the axis of motion. The proposed control law and lyapunov function guarantee asymptotic stability from all initial values except one singular point.
Archive of Applied Mechanics
We are interested in the stability properties of the equilibrium states of a simple mechanical system with unilateral contact and Coulomb friction. First, we give a complete description of the set of solutions that the equilibrium problem may have, depending on the stiffness coefficients, on the external forces and on the friction coefficient. In t...
Committee Chair: Tsiotras, Panagiotis; Committee Member: Haddad, Wassim M.; Committee Member: Johnson, Eric; Committee Member: Taylor, David G.; Committee Member: Verriest, Erik I.
Journal of Intelligent and Robotic Systems
This paper considers the control of a linear drive system with friction and disturbance compensation. A stable adaptive controller integrated with fuzzy model-based friction estimation and switching-based disturbance compensation is proposed via Lyapunov stability theory. A TSK fuzzy model with local linear friction models is suggested for real-tim...
We consider the problem of function of state plus unknown input estimation of a linear time-invariant system using only the measured outputs. Two reduced-order input estimators built upon a state functional observer are proposed. The first is an extension of a state/input estimator, while the second is based on adaptive observer design technique. T...
This paper deals with the control design for optical storage drives. A nonlinear design is suggested to overcome the tradeoff between disturbance rejection, in the sense of tracking error reduction during low-frequency shock and vibration, and playability, in the sense of sensor noise tracking during high-frequency disc surface defects. Based on a ...
This work discusses how to compute stability regions for nonlinear systems with slowly varying parameters using frozen stationary linearization. It is shown that larger stability regions can be obtained as compared to traditional approaches using recent stability results for linear parameter-varying systems.
In this article exponential stability of the closed loop for the Saab AB VEGAS model controlled by a gain-scheduled linear fractional transformation controller is investigated for time-varying Mach-number. The analysis is based on parameter-dependent Lyapunov-functions which are obtained by investigating feasibility of linear matrix inequalities.
This article addresses the problem of stability of impulsive control systems whose dynamics are given by measure driven differential inclusions. One important feature concerns the adopted solution which allows the consideration of systems whose singular dynamics do not satisfy the so-called Frobenius condition. After extending the conventional noti...