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In this paper we derive two classes of flight trajectories for tracking ground based objects with micro air vehicles. The first class of flight trajectories, called longitudinal trajectories, consists of switching between clockwise and counter clockwise orbits so that the average velocity of the MAV along the direction of motion is equal to the velocity of the ground target. The second class of flight...
In this paper we analyze the reason why the QR-factorization is a very useful method for estimate the atmospheric delay in the unwrapped step of the SAR interferometric processing. We compute the solution of phase delay parameter model and confront the result with the GPS data metrics and the result from the Saastamoinen model. It is important to develop the new method for estimate the atmospheric...
This paper applies different control design methods to a tethered satellite system (TSS) to investigate essential control properties of this under-actuated and nonlinear system. When the tether position in the orbit plane is controlled by the tether current, out of orbit plane motions occur as an unwanted side effect, due to nonlinear interaction with the Earth’s magnetic field. This paper focus on...
Fault detection and isolation is a key component of any safety-critical system. Although diagnosis methods based on discrete event systems have been recognized as a promising framework, they cannot be easily applied to systems with complex continuous dynamics. This paper presents a novel approach for discrete event system diagnosis of continuous systems based on a qualitative abstraction of the measurement...
In smart-power IC technologies the trend toward more functional integration is expected to intensify further, producing more compact, efficient, and user-friendly power modules. It looks that in the foreseeable future it will be possible to connect a motor to a controller without specially designed electronics. The paper is focused on the design strategy of next generation single-chip smart inverters...
The work considers the control synthesis in the presence of a parametric uncertainty, with application to electrohydraulic servos actuating primary flight controls. The obtained control law, containing a dynamic updating of uncertain parameter, renders the closed loop system stable and guarantees asymptotic tracking of position references. The uncertain parameter is on line adjusted, using in synthesis...
A robust version of the output controller design for discrete-time systems is introduced. Instead of a single stable point a stable polytope (or simplex) is preselected in the closed loop characteristic polynomials coefficients space. A constructive procedure for generating stable simplexis is given starting from the unit hypercube of reflection coefficients of monic polynomials. This procedure is...
Functional Series Time-dependent AutoRegressive (FS-TAR) models constitute an important class of models for non-stationary signal modelling. However, the asymptotic properties of “general” (not necessarily periodically evolving) FS-TAR estimators are not, yet, well understood. In the present study, the problem of establishing an asymptotic analysis framework capable of accounting for “general” FS-TAR...
The work presented in this paper deals with the process of transfer function identification by using self-oscillation method (autotuning identification method). The algorithm is given in a general matrix form and some modifications are introduced. The modifications of the algorithm include augmentation of the initial algorithm for Type k systems, systems with delays and discrete-time systems. The...
The problem of residual generation is discussed for linear singular systems with a finite number of commensurable point delays using as models systems with coefficients in a ring. Using the geometric notion of conditioned invariant submodule, suitably defined for singular systems over a ring, a procedure is presented for constructing a residual generator for the fault detection and isolation for singular...
Previous research in the modeling and simulation of hybrid systems led to the development of a general hybrid systems modeling language (HSML). In more recent work, we have implemented this concept in software. The standard MATLAB model framework and integration algorithms have been extended to support state-event handling in continuous-time components and to deal with embedded discrete-time components,...
In this paper, we propose a design methodology for the tracking of spacecraft attitude. The plant (spacecraft model) is a second order nonlinear multi-input-multi-output system. We stabilize the plant using state feedback. The stability of the closed-loop is assured using a Lyapunov function. Then the step response of the closed-loop system is used to design PID controller using standard classical...
A variable speed wind energy converter operation control system based on stochastic dynamic optimisation was developed. The task of this control system is to set the appliance to the optimal operation point. Here the convergence and the computation power demand are vital for the accurate operation of the control. This nonlinear optimisation structure was adapted for real time control operation with...
This paper proposes a nonlinear tracking control method for underactuated ships based on a unified kinematic and dynamic model. There are several literatures using backstepping-based controllers, which usually results in the complicated control structures and the restriction on the reference trajectories. To obtain a controller with much simpler structure and less restriction on the reference trajectory,...
An adaptive control algorithm for the elimination of torque and velocity ripples in the alternating current (AC) permanent magnet (PM) motor control systems is presented in this paper. A model of AC PM motor system includes n sinusoidal disturbances is first developed. The internal model principle (IMP) is then applied to design a controller to eliminate the torque and velocity ripples without estimating...
In this paper we build on, and extend our previous work on automated nuclear search, by taking the principle of a bidirectional interaction between perception and the sensor management to the implementation level. In the algorithm that we implement in hardware, a model of the underlying physical process is used to guide measurement, which then closes the loop by updating the model. Realization of...
This paper invests in the potentiality of transmission capability flexibilization of power system to improve the margin of stability system. Series compensation is introduced to change the transmission line reactance by means of controlled switching strategy. This switching attends the concepts of variable structure control to carry the system on stabilization sliding mode where the oscillations are...
In this paper, we investigate what constitutes the least amount of a priori information on the nonlinearity so that the linear part is identifiable in the non-Gausian case. Three types of a priori information are considered including quadrant information, point information and locally monotonous information. In all three cases, identifiability has been established and corresponding identification...
This paper presents a control method using an adjusting output-limiter for stable haptic rendering in a virtual environment. In a simulation of force-reflecting interaction with deformable objects in a virtual environment, a quick computation of the accurate impedance of deformable objects is rare. This is particularly true when physics-based models, such as tensor-mass models or mass-spring models,...
A novel technique is presented for organizing swarms of robots into formation utilizing artificial potential fields generated from normal and sigmoid functions. These functions construct the surface swarm members travel on, controlling the overall swarm geometry and the individual member spacing. Limiting functions are defined to provide tighter swarm control by modifying and adjusting a set of control...
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