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.
Studies have shown that feedback linearization can provide an effective controller for many types of nonlinear systems. It is known, however, that these controllers are not robust, in particular to model uncertainties. Recent work on sensitivity theory has shown that it can provide the least conservative design for robust feedback linearization. This is achieved by adjusting the control input to minimize...
Port Hamiltonian systems are usually passive with respect to port variables that are power conjugate (eg: voltage and current, force and velocity) and this lead to energy shaping control methods. But systems with ‘dissipation obstacle’ cannot be controlled using these port variables and therefore we need to search for alternative passive maps. One option is within the Brayton Moser framework, where...
We present an approach to passivate a class of discrete time switched nonlinear systems under arbitrary switching. Using switched storage functions, we derive a linear matrix inequality condition for strict input passivity of discrete time switched nonlinear systems. When the switched system is non passive, we design a state feedback controller to ensure system passivity under any admissible switching...
In many applications of compressed sensing, coherence of the matrix A plays an important role in theoretical guarantees for obtaining sparse solutions to linear system of equations, y = Ax. For a given matrix G with trivial right null space, the system Gy = GAx is equivalent. In this paper we establish that if G is a random matrix with i.i.d. realizations of Gaussian or Bernoulli random variables...
In this paper neural network based adaptive controller has been designed for underactuated systems. To control the actuated joint variables collocated partial feedback linearization is used while the unactuated joint variables are controlled using non-collocated partial feedback linearization. Radial Basis Function Networks are used for approximation of inertia, friction, gravitation, centrifugal...
The paper presents a time domain based modelling and identification of real-time control system in terms of stable dynamics of first order plus dead time (FOPDT). An asymmetrical relay is commissioned for yielding limit cycle output from unknown plants. Thereafter, the limit cycle information is utilized in equations for real-time plant dynamics to be identified. Mathematical expressions based on...
This paper presents a method for remaining useful life (RUL) estimation of lithium-ion batteries based on the internal resistance growth model using the particle filtering (PF) approach. In the following study, the internal resistance growth of a battery have been considered as the ageing parameter in terms of an empirical model developed based on electrochemical impedance spectroscopy (EIS) test...
The problem of sample size determination (SSD) for any black box model is addressed in this work. Four novel SSD algorithms namely HC, SOOP, HC+SOOP and V-SOOP, based on hypercube sampling, space filling and optimization study are proposed to tackle the issues of over-fitting, accuracy and computational speed of surrogate models. In this version, the novel algorithms are shown to run simultaneously...
System identification (SI) using small samples is a problem of interest in several applications. However, parameter estimation in these situations is a challenge since classical identification techniques (based on prediction-error methods) are guaranteed to be efficient and consistent only under asymptotic (large sample) conditions. In addition these techniques need the knowledge of delay and order...
Through this paper we introduce an exclusive library sysid for system identification in the R® platform. This open-source library, the first of its kind on this platform, is designed primarily for classroom training and academic purposes. The library contains routines for input design, simulation and standard estimation methods for understanding the subject of and developing data-driven models for...
This paper proposes a novel integrated robust system identification and state of charge estimation of Li-ion battery. A finite time extended state observer is used for state of charge (SOC) estimation of Li-ion battery. A relay feedback test has been adopted to yield accurate battery parameters in noisy environment. New identification method using state space based relay feedback approach is employed...
This paper develops a generalized extended state observer based control (GESOBC) for nonlinear systems with matched and mismatched uncertainties. The control law is designed based on estimated states via generalized extended state observer (GESO). The effect of external disturbances as well as parametric uncertainties are nullified by introducing disturbance compensation gain. The designed controller...
Backstepping design is a powerful method for stabilization and tracking of strict feedback nonlinear systems which find applications in practical fields like robotics, aerospace, process control, etc. However the presence of uncertainties in system dynamics complicates the control design procedure. In recent past, high gain disturbance observer based backstepping design has received considerable attention...
A new nonlinear filtering algorithm based on sparse-grid Gauss-Hermite filter (SGHF) incorporated with the technique of algorithm adapting to dimensions based on their nonlinearity, is presented. The motive of this work is to reduce the computatioanl load of SGHF, while maintaining similar filtering accuracy. This is achieved by implementing adaptive tensor product to construct the multidimensional...
The conventional Bayesian framework of filtering is based on the assumption that the measurements are available at each time-step without any delay. But in real-life problems, measurements may be randomly delayed in time. In this paper, we modified the unscented Kalman filter (UKF) for arbitrary time delayed measurements. With the help of simulation results, it has been shown that the proposed filter...
In this paper, a path planning algorithm is presented in a dynamic environment with moving and deforming irregularly shaped obstacles using the concept of collision cones. A method to determine the collision cone of an irregularly shaped obstacle using radar signal return is introduced. No restrictions are placed either on the obstacle shape or on its velocity. Simulation results are given to validate...
The current era has witnessed a huge demand across the globe for stringent pointing accuracy for Earth observation imaging payloads. This paper brings to light a novel improved controller for high precision pointing accuracy and jitter reduction. The pointing accuracy is judged in terms of the reference tracking capability of the imaging satellites. This improved precision pointing technique aims...
In this article, an adaptive model following control of a nonlinear multi-input multi-output (MIMO) coupled system with unknown parameters is considered. The decoupling matrix of the system is assumed to be singular, so that the system can not be decoupled by static state feedback. A dynamic state feedback with nonlinear structure algorithm is applied to design the controller. An observer is used...
This paper considers adaptive relative attitude tracking control of two spacecraft formulated in SO(3) using line-of-sight measurements. The objective is to control the attitudes of individual spacecraft with unknown moment of inertia so as to track a specified time-varying relative attitude trajectory. We propose an estimation scheme for the moment of inertia. Proposed control torques and estimation...
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.