The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper presents a yaw control problem for ship steering using a complex fourth order Nomoto model. A linear matrix iinequality (LMI) based H robust control to deal with poles on imaginary axis is applied to solve the yaw control problem for ship steering. The model uncertainty of ship steering problem is tackled using μ-synthesis control approach. The tracking ability and robust stability of H...
In this paper, we establish a robust optimal control law for a class of continuous-time uncertain nonlinear systems by using a neural-network-based model-free policy iteration approach. The robust control law of the original uncertain nonlinear system is derived by adding a feedback gain to the optimal control law of the nominal system. It is proven that this robust control law can achieve optimality...
Buck converters are still used as an efficient step down DC-DC converters for constant load voltage for many power supply applications under variable input voltage and different loading conditions. In most of the applications DC-DC converters are controlled by either voltage or by current mode controller. DC-DC converters exhibit non-linear behavior due to switching, hence controller design comes...
A quantitative feedback theory based systematic design procedure is proposed for two-inductor boost dc-dc converter. The two-loop design proposed in this paper is effective in handling the uncertainties, both in model as well as in converter parameters. Compatible models are formulated, in discrete-time domain, to achieve this task. Minimum stability margin is enforced so as to keep the system within...
This paper provides a comparative study of distributed formation control approaches for multi-agent systems (MAS) subject to uncertain and time-varying communication topologies. A unified framework is proposed to describe this kind of systems for different control schemes. Based on that, two control schemes are examined: One is a robust controller design based on the small gain theorem with the ℓ1...
A global task coordinate frame (GTCF) based learning adaptive robust controller (LARC) is practically synthesized for an industrial X-Y linear-motor-driven stage to achieve not only good parametric adaptation ability and uncertain disturbance robustness, but also excellent transient/steady-state contouring performance. With the employment of GTCF which is globally based on the shape of the desired...
Flat filtering constitutes a reinterpretation of Generalized Proportional Integral Control (GPIC) in the form of robust Classical Compensation Networks (CCN). Roughly speaking, any linear controllable system can be output regulated with the help of a well tuned filter and a suitable cascaded linear combinations of the internal states of such filter. Here, it is shown that such classical tool is also...
Robust stability synthesis of a class of uncertain parameter-varying first-order time-delay systems is presented in this paper. Internal model principle is used to design a robust control using ℋ∞ small-gain theorem. The closed-loop system robustness is investigated against bounded variation of the parameters and sensitivity analysis is performed to determine the stability conditions and provide a...
In this paper, the computation of closed-form convex combinations is considered. In many control tasks, convex combinations play a crucial role, thus requiring an efficient computation. This is the case for online control of fast dynamical systems, in which the control algorithms rely on convex combinations, for example robust control of linear parameter-varying systems. On the other hand, for formal...
We propose a new method for controlling rigid robot manipulators guaranteeing that a user-defined tracking performance is ultimately met while facing uncertain system dynamics and input disturbance. Our control approach is based on the passivity-based control technique and eliminates the limitations of existing methods (e.g. impractical tuning to avoid chattering and difficult estimation of uncertainty...
In this paper, a strategy is established to design the robust controller for a class of continuous-time nonlinear systems with Lurie uncertainties.The uncertainty is decomposed into matched and unmatched components, and an augmented control is introduced for the unmatched uncertainty. An optimal control algorithm based on Hamilton-Jacobi-Bellman(HJB) equation is proposed for the design of a bounded...
The inherent rate-dependent hysteresis in smart actuators hinders their wider applicability in practical engineeering. In this paper, based on the rate-dependent Hammerstein model, a 2 DOF control scheme with a robust controller combined with a hysteresis compensator is proposed for tracking control of smart actuators. The hysteresis compensator is first connected in cascade with an actuator to cancel...
We revisit the issue of gain-scheduled versus robust control with a focus on matrix inequalities. It has been established that for uncertain continuous-time linear systems that depend affinely on the uncertainty, gain-scheduled stabilizability implies robust stabilizability. That is, as far as stabilizability is concerned, using a more complex gain-scheduled controller brings no advantage. In the...
In this article, the ball and beam trajectory tracking problem is tackled using a robust Generalized Proportional Integral (GPI) Controller. The controller is developed on the basis of the tangent linearized system model around the equilibrium point. The approximate linearized system is differentially flat, and hence, controllable. Flatness reveals that the resulting linearized system has an interesting...
A method is presented for synthesizing output estimators for a class of continuous time, uncertain, linear parameter-varying (LPV) systems. The uncertain system is described as an interconnection of a nominal LPV system and a block structured perturbation. The nominal LPV system is “gridded” over the space of parameters, with the state matrices being arbitrary functions of the parameters. The input/output...
In this article, we propose sufficient conditions for robust observer-based control of uncertain linear systems with polytopic uncertainties and unknown disturbances. The observer and the controller gains are obtained from the solution of a convex-optimization problem. Mixed performance constraints are imposed on the design in order to minimize the effects of the unknown disturbances on the overall...
This paper presents a novel tracking controller for a three degrees-of-freedom permanent magnet spherical actuator (PMSA). The controller is designed on the basis of the establishment of dynamics model under uncertainties. The major construction of the controller lies in the use of the matrix regressor to isolate unknown parameters from the PMSA. Moreover, sliding-mode control and robust control are...
The sampling points in one cycle of 400 Hz inverter is 8 times less than that of 50 Hz inverter, resulting in lower control accuracy and larger static error in 400 Hz power supply system. According to the characteristics of the 400 Hz inverter, this paper establishes a mathematical model for single-phase solid-static power supply system. The changes in line impedance and load can be considered as...
Voltage converter circuits are fundamental components in power electronics applications. However, their paramount role on various appliances due to their well-known benefits comes together with difficulties and restrictions for their modeling and control. A buck converter is naturally subjected to non-linearities, time-dependency, noise, and parameter variations. Altogether, it is difficult to provide...
In this paper an iterative procedure is developed for obtaining the maximally permissive solution for the problem of robust nonblocking supervisory control of discrete-event systems assuming full event observation. In the robust control problem, the plant model belongs to a finite family of discrete-event models, each with its own design specification. It is shown that the procedure developed in this...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.