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This article presents a novel obstacle avoidance algorithm. Using a combination of fuzzy logic and gain scheduling theories, a new methodology that reduces computational costs compared to conventional fuzzy methodologies, specially when the variables to be controlled are too many. For comparison purposes, a potential field algorithm was implemented. Both algorithms are tested in a series of experiments to determine if the new algorithm is at least as good as the potential field algorithm. The metrics defined for these experiments are: the number of times that the agent collides (collisions), the time spent to finish a traced course (time spent) and the remaining stamina of an agent at the end of an experiment (stamina consumption). The results show that the proposed algorithm achieve a low level of collisions. Also, the proposed algorithm shows a considerable improvement in the time spent for the completion of the proposed tasks. Last but not least, the results demonstrate a considerable reduction in the stamina consumption using the proposed algorithm over the potential field algorithm. [ABSTRACT FROM PUBLISHER]

The article discusses a study which investigated gain scheduling and output feedback control design for an offshore floating wind turbine. The software FAST was used to obtain the wind turbine model. Linear matrix inequalities (LMIs) are solved using YALMIP interfaced with MATLAB, while the controller was tested on the fully nonlinear system.

Internet users rely on the good capabilities of TCP/IP networks for dealing with congestion. The network delay and the number of users change constantly, which might lead to transmission problems. Usually, they are handled following approaches such as drop tail or random early detection (RED) algorithms. During the last few years, automatic control techniques are providing practical solutions. Moreover, if there are wireless links, congestion control is more difficult to detect. This paper presents a methodology to design a PID controller with a linear gain scheduling that allows a network with wireless links to deal with control congestion under a variety of configurations. The proposed technique is demonstrated through non-linear simulations and compared with the classical PID [ABSTRACT FROM AUTHOR]

This paper presents a new quadratic stability-preserving state-space realization and quadratically stabilizing observer-based controller design for Linear Parameter Varying (LPV) plant, which is combined with a set of local vertex LTI plants. A two-step procedure is taken to design a quadratically stabilizing observer-based controller for LPV plant. First, according to the stabilizabilities of local LTI plants, state-feedback gain matrices and Lyapunov matrices could be solved for these local plants with linear matrix inequality technique, independently. With these Lyapunov matrices, a proper state space realization of LPV plant is provided. Second, based on the state space realization, a quadratically stabilizing observer-based controller is obtained. [ABSTRACT FROM PUBLISHER]

In this paper, we propose a gain scheduled reference governor for control of systems with constraints on the state and/or input variables. We use the reference governor with outer feedback constructed via model following control method. We apply this control scheme to design of long seek control of hard disk drives. To achieve short seek time for long seek distance problems, we consider gain scheduling with the reference governor; more precisely, we switch feedback gains according to the location of the state. Moreover, we examine the usefulness of the proposed method by applying it to benchmark problems of hard disk drive control. [ABSTRACT FROM PUBLISHER]

PID controllers have been employed in servo systems for decades. It is well known that an underdamped system has a fast response but accompanied by undesired overshoot, whereas an overdamped system has no oscillation at all but its response is too slow. We propose a setpoint gain scheduling scheme for PD-type controllers using fuzzy logic, which is simple and effective to implement in the industry, to take the advantages of fast response and oscillation suppression. Our objective is to move a positioning system to a target position and have it settle down as soon as possible. In order to optimize the parameters, we use Powell's method to provide conjugate direction search and the golden section method to find the optimal step size along the search direction. A ballscrew linear stage is used to demonstrate the effectiveness of our proposed scheme successfully. In an experiment of 80 mm movement, it takes additional 0.01 s only to settle down after 0.32 s move time by using the proposed method, whereas it takes additional 0.23 s to settle down by using the auto-tuned conventional PD-type controller. [ABSTRACT FROM PUBLISHER]

In this paper revised model of the IEEE working group recommended is used for simulation of transient response of hydro turbine converted to state space model and verification was made using measurements of transients from real Hydro Power Plant (HPP). Nonlinear mixed model controller was designed and implemented into complete HPP simulation model and compared with PID with real parameters used in HPP, and with adjusted PID parameters with consideration of smallest frequency error. Verification of performance of the model was made comparing model response with measured load rejection, which is worst case of HPP operation. [ABSTRACT FROM PUBLISHER]

In this study, a fuzzy tuned SMC based architecture is designed for the control of PLL based frequency synthesizers. The proposed approach, offering a continuous tuning of chattering property, is demonstrated to be more effective over classical, intelligent and traditional sliding mode control methods for the fast locking and low phase noise requirements of PLL based frequency synthesizers in frequency hopping spread spectrum communication and radar applications. The obtained simulation results are compared with those of a PID, a Fuzzy Gain Scheduled Control, a SMC, and traditional FS controller design and it has been concluded that the settling time and the phase noise of the frequency synthesizer can be optimized using the developed fuzzy tuned SMC based PLL. [ABSTRACT FROM PUBLISHER]

For a class of uncertain discrete-inputting time lag systems, according to the characteristics of augmented model's input matrix, by making use of the gain scheduling and multi-step control set, robust predictive control algorithm with the parameter-dependent feedback law is proposed. The simulation results show the advantages and disadvantages of two algorithms and the robust model predictive control algorithm with gain scheduling and multi-step control set can improve the control performance of the system better than pure application multi-step control set. [ABSTRACT FROM PUBLISHER]

This paper presents a systematic approach for nonlinear control design by using the gain scheduling technique to insure the transition of a nonlinear dynamical process from an actual operating condition to a desired one. The first step in this approach is represented the nonlinear system in neighbourhoods of equilibrium points by a family of uncertain linear systems. The second step is the use of robust control methods based on LMIs that assure local stability in a non-infinitesimal state space domain. This last point permits to determine the global control law. A simple numerical experiment is provided to illustrate both the effectiveness of the synthesis and the performance achieved. [ABSTRACT FROM AUTHOR]