Search results for "Systems engineering"
showing 10 items of 1230 documents
H∞ static output-feedback control design with constrained information for offshore wind turbine system
2013
Abstract This paper deals with H ∞ static output-feedback control design with constrained information for offshore wind turbines. Constrained information indicates that a special zero–nonzero structure is imposed on the static output-feedback gain matrix. A practical use of such an approach is to design a decentralized controller for a wind turbine. This will also benefit the controller in such a way that it is more tolerant to sensor failure. Furthermore, the model under consideration is obtained by using the wind turbine simulation software FAST. Sufficient conditions to design an H ∞ controller are given in terms of Linear Matrix Inequalities ( LMI s ). Simulation results are given to il…
THE METAMODEL: A STARTING POINT FOR DESIGN PROCESSES CONSTRUCTION
2010
The construction of ad-hoc design processes following the Situational Method Engineering (SME) paradigm is currently carried out by adopting a set of phases for which, until now, no well defined techniques and guidelines have been established. The consequence is that organizations are very dependent on method designers' skills. In this paper, we propose an approach based on SME for constructing customized agent oriented design processes. Our approach adopts the metamodel as the most important factor leading to the selection and assembly of method fragments and an algorithm for establishing the instantiation order of metamodel elements. The algorithm makes the proposed approach repeatable a…
Analysis of Offshore Knuckle Boom Crane - Part One: Modeling and Parameter Identification
2013
This paper presents an extensive model of a knuckle boom crane used for pipe handling on offshore drilling rigs. The mechanical system is modeled as a multi-body system and includes the structural flexibility and damping. The motion control system model includes the main components of the crane's electro-hydraulic actuation system. For this a novel black-box model for counterbalance valves is presented, which uses two different pressure ratios to compute the flow through the valve. Experimental data and parameter identification, based on both numerical optimization and manual tuning, are used to verify the crane model. The demonstrated modeling and parameter identification techniques target…
A state-space approach to mathematical modeling and parameters identification of vehicle frontal crash
2014
In this paper a state-space estimation procedure that relies on the time-domain analysis of input and output signals is used for mathematical modeling of vehicle frontal crash. The model is a double-spring–mass–damper system, whereby the front mass and real mass represent the chassis and the passenger compartment, respectively. It is observed that the dynamic crash of the model is closer to the dynamic crash from experimental when the mass of the chassis is greater than the mass of the passenger compartment. The dynamic crash depends on pole placement and the estimated parameters. It is noted that when the poles of the model are closer to zero, the dynamic crash of the model is far from the…
2013
Today, integration of supply networks (SNs) out of heterogeneous entities is quite challenging for industries. Individualized demands are getting continuously higher values in the global business and this fact forces traditional businesses for restructuring their organizations. In order to contribute to new performances in manufacturing networks, in this paper a collaborative approach is recommended out of modularity structure, cloud computing, and make-to-upgrade concept for improving flexibility as well as coordination of entities in networks. A cloud-based framework for inbound and outbound manufacturing is introduced for complying with the production of individualized products in the tu…
Time-Optimal Synthesis for Three Relevant Problems: The Brockett Integrator, the Grushin Plane and the Martinet Distribution
2015
We construct the time-optimal synthesis for 3 problems that are linear in the control and with polytopic constraints in the controls. Namely, the Brockett integrator, the Grushin plane, and the Martinet distribution. The main purpose is to illustrate the steps in solving an optimal control problem and in particular the use of second order conditions. The Grushin and the Martinet case are particularly important: the first is the prototype of a rank-varying distribution, the second of a non-equiregular structure.
Composite nonlinear feedback control for path following of four-wheel independently actuated autonomous ground vehicles
2015
This paper studies the path following control problem for four-wheel independently actuated (FWIA) autonomous ground vehicles (AGVs) through integrated control of active front-wheel steering (AFS) and direct yaw-moment control (DYC). A modified composite nonlinear feedback (CNF) strategy is proposed to improve the transient performance and eliminate the steady-state errors in the path following control considering the tire force saturations, in the presence of the time-varying road curvature for the desired path. The path following is achieved through vehicle lateral and yaw control, i.e., the lateral velocity and yaw rate are simultaneously controlled to track their respective desired valu…
Scalable and Privacy-Preserving Admission Control for Smart Grids
2015
International audience; Energy demand and production need to be constantly matched in the power grid. The traditional paradigm to continuously adapt the production to the demand is challenged by the increasing penetration of more variable and less predictable energy sources, like solar photovoltaics and wind power. An alternative approach is the so called direct control of some inherently flexible electric loads to shape the demand. Direct control of deferrable loads presents analogies with flow admission control in telecommunication networks: a request for network resources (bandwidth or energy) can be delayed on the basis of the current network status in order to guarantee some performanc…
Convergence-based Analysis of Robustness to Delay in Anti-windup Loop of Aircraft Autopilot∗∗This work was supported by Russian Scientific Foundation…
2015
Abstract The windup phenomenon is interpreted as a consequence of the convergent property absence for system with a saturation. This makes it possible to use the frequency-domain criterion for analysis of anti-windup augmentation in the case of stable and marginally stable plants. Based on this approach, robustness of the systems with respect to time delay in the anti-windup loop is examined and the approach for an optimal choice of the static anti-windup gain is proposed. An application of the convergence-based anti-windup control strategy to aircraft flight control for the case of time-delay in the anti-windup loop is described and studied by simulations.
UAV control with switched GNSS-Estimator navigation system∗∗This work was supported by Russian Scientific Foundation (project 14-21-00041) and Saint-…
2015
Abstract In the paper the switched GNSS-Estimator navigation system, recently proposed by the authors, is described and numerically studied in the framework of evaluation of the overall UAV control system accuracy.