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In many industries there is a need for a flexible system, which is capable of picking up some objects of various shapes, weights, and colors with arbitrarily position and orientation. Such system requires recognition and guiding sub-systems. The recognition system includes target function for the recognition sub-system and relation between object characteristics and recognition target. The laser sensor system can be used for such object recognition. Wire-based telemetry and control systems can cause many problems in shop floors and factories, and so there has been a strong growth of interest in wireless guidance like vehicles equipped with laser guiding and navigation systems. This article... 

In this paper, a new approach for controlling the sway angle of the load in trolley cranes is presented which is based on the flexibility of the cable and variation of its length by the time. The crane dynamics has been described by hybrid PDE and ODE equations which uses the PDE as the equations of motion for the flexible cable and ODE for those of the trolley and the load. The purpose of the controller is to transport the load to the desired position and to eliminate its sway angle at the destination. The control law is based on the Lyapunov's second method. The efficiency of the proposed controller is demonstrated via various simulations  

In this paper, a robust sliding mode control for a flexible transmission system is presented. This system has two very oscillatory vibration modes subject to large load variation which makes the control of it be difficult. A set of design specification in time domain is to be met by a single controller on each of the three main plant models. Furthermore the tracking problem in the presence of disturbance and load variation is investigated. Results show good performance of the proposed controller. In this approach, in order to estimate the hidden states of the flexible transmission system, an observer based on sliding mode control is used. © 2004 IEEE  

An application of a continuous-time H∞ control to a flexible transmission system is presented. This approach has been proposed in order to assure high control performance in the presence of large load variation on the system. In this approach, the loading variations are considered as the multiplicative perturbation of the nominal plant. The desired specifications are enforced in the H∞ problem as the constraints on weighting functions. After an initial design procedure, the parameters of weighting functions, in order to obtain the desired performances, are tuned and then the final weighting functions are derived. The simulation results for three different loadings are given and compared  

New industries and production plants require a flexible system, which is capable of picking up objects of various shapes, weights, and colors with arbitrary position and orientation. Such a system also needs recognition and guiding sub-systems. The recognition system includes target function for the recognition sub-system and relation between object characteristics and recognition target. The laser sensor system can be used for such object recognition. Wire-based telemetry and control systems can cause many problems in shop floors and factories, and so there has been a strong growth of interest in wireless guidance like vehicles equipped with laser guiding and navigation systems. For the... 

This paper presents a novel flexible control strategy for Unified Power Quality Conditioner (UPQC), which achieves more flexibility in compensation of power quality disturbances as compared to the existing methods. The proposed control strategy provides priority-based compensation as well as full and standard-based compensation considering the rating of series and shunt parts of a UPQC. The priority-based compensation is done based on the compensation priority among different power quality disturbances. In this control strategy, an on-line estimation of different voltage and current disturbances is required. For this purpose, a Unified Adaptive Power Quality Estimator (UAPQE) has been... 

The increasing variability of renewables and volatile chronological net-load in power grids engenders significant risks of an uncertain sufficiency of flexible capacity. Although considerable advances in power grid flexibility assessment have been made, modeling the effect of temporal correlations associated with wind generations on the system flexibility provision capability has remained a challenge. This paper proposes a novel UC-time-scale security-constrained affinely robust formulation for wind-originated uncertainty sets in order to evaluate the system flexibility capacity over time. An efficient model based on duality theorem and affine policy is proposed to assess a secure region in... 

Flexible all-solid-state supercapacitors are promising electronic devices have been developed in the past decade. Recent efforts to develop such systems are as to construction of free standing electrodes with high specific capacitance. Among these developments, construction of carbon-based current collectors, with high surface areas and good mechanical properties via a facile and economic way, has been taken a great deal of attention. In this study, porous graphene were used as current collector for placement of the carbon fibers functionalized with polyaniline, to prepare a free-standing supercapacitor electrode through a new and facile method. This method begins through blending of the... 

Flexible manufacturing systems (FMS) should be able to respond to changing manufacturing requirements and environments. From the layout point of view, FMS need to be rearranged to fit the new requirements. However, rearranging the layout is often undesirable due to its unpredicted high costs and production disruption. This paper proposes a practical approach to mitigate the effects and repercussions of changing environments and avoid rearranging the layout. A robust layout approach is presented, where changes in product demand and mix are absorbed by altering product routes and not rearranging the layout. In this approach, the problem is decomposed into two sub-problems: sub-problem 1 (SP1)... 

This paper focuses on the sliding mode control which incorporates a fuzzy tuning technique. In this scheme, first, a control input based on classical sliding mode control is designed. Then, for performance enhancement and chattering elimination, an additional fuzzy control term is used together with the control signal. Furthermore the Lyapunov stability method is used to prove the asymptotic convergence of control strategies. To illustrate the usefulness of the proposed approach, classical and fuzzy sliding mode control are both applied to a flexible transmission system. The results verify the validity of the proposed control scheme. © 2004 IEEE  

Under new reregulation environment an open access to transmission system is desired. Transmission system operators (TSOs) are encouraged to use the existing facilities more efficiently. This paper focuses on the evaluation of the impact of FACTS devices on Available Transfer Capability (ATC) and its enhancement. Genetic algorithm is used for optimisation process of the best location of SVC as a FACTS device. Improvement of voltage profile as well as TTC enhancement is achieved by applying a proposed methodology through some case studies  

An improved method for deriving elastic generalized coordinates is considered. Then Kane's equations of motion for multibody systems consisting of an arbitrary number of rigid and elastic bodies is presented. The equations are in general form and are applicable for any desired holonomic system. Flexibility in choosing generalized speeds in terms of generalized coordinate derivatives in Kane's method is used. It is shown that proper choice of a congruency transformation between generalized coordinate derivatives and generalized speeds leads to equations of motion for holonomic multibody systems consisting of an arbitrary number of rigid and elastic bodies. These equations are decoupled in... 

The time-varying structural reliability of an aeroelastic launch vehicle subjected to stochastic parameters is investigated. The launch vehicle structure is under the combined action of several stochastic loads that include aerodynamics, thrust as well as internal combustion pressure. The launch vehicle's main body structural flexibility is modeled via the normal mode shapes of a free-free Euler beam, where the aerodynamic loadings on the vehicle are due to force on each incremental section of the vehicle. The rigid and elastic coupled nonlinear equations of motion are derived following the Lagrangian approach that results in a complete aeroelastic simulation for the prediction of the... 

Virtual power plant (VPP) aggregates the capacity of diverse distributed energy resources (DERs) dispersed around the network and creates an individual operating portfolio from the composition of DERs characteristics. VPP can schedule the DERs to provide energy and different types of reserve services in order to trade in wholesale electricity markets or provide network services. In this chapter, an optimization model of VPP to provide energy and reserve is addressed. In this regard, diverse DERs’ energy and reserve models are mentioned and optimization models of VPP to aggregate DERs in order to provide energy and reserve and make profit in wholesale markets are regarded. Furthermore, a... 

Virtual power plant (VPP) aggregates the capacity of diverse distributed energy resources (DERs) dispersed around the network and creates an individual operating portfolio from the composition of DERs characteristics. VPP can schedule the DERs to provide energy and different types of reserve services in order to trade in wholesale electricity markets or provide network services. In this chapter, an optimization model of VPP to provide energy and reserve is addressed. In this regard, diverse DERs' energy and reserve models are mentioned and optimization models of VPP to aggregate DERs in order to provide energy and reserve and make profit in wholesale markets are regarded. Furthermore, a... 

An efficient algorithm for the design optimization of the compressible fluid flow problem through a flexible structure is presented. The methodology has three essential parts: first the behavior of compressible flow in a supersonic diffuser was studied numerically in quasi-one-dimensional form using a flux splitting method. Second, a fully coupled sequential iterative procedure was used to solve the steady state aeroelastic problem of a flexible wall diffuser. Finally, a robust Genetic Algorithm was implemented and used to calculate the optimum shape of the flexible wall diffuser for a prescribed pressure distribution. © 2006 Elsevier Ltd. All rights reserved  

Using some agent variables, the general structure of the dynamic model of a spatial mobile robot with N long spatially flexible links and N revolute joints has been exposed. It is composed of a set of 5N + 6 nonlinear coupled partial differential motion equations under the influence of the boundary conditions. Non-conservative forces/moments have been neglected. While being considered, the general structure of the dynamic model will not change, but a few exciting/damping terms will arise within the agent variables. The base of the robot is an unconstrained rigid body in space and the links as 3D Euler-Bernoulli beams undergo tension-compression, torsion and two spatial bendings while elastic... 

Attitude and vibration control of a general form of flexible satellites is addressed in this paper. Partial differential dynamic equations are derived considering new details such as multi sectioned solar panels and elastic connections between main hub and solar panels. Boundary control approach is adopted to eliminate simplification errors of discrete models, using just one actuator in the hub. Asymptotic stability of attitude dynamics is proved for a group of boundary controllers and necessary conditions for asymptotic stability of vibrations are discussed. Being independent of modeling accuracy and using easily measurable feedbacks are among advantages of the proposed class of... 

Electric spring (ES) as a breakthrough in power electronics has led to a revolution in demand-side management. This paper presents flexible power management (FPM) of a networked microgrid (MG) in the presence of renewable energy sources (RESs) and flexibility sources (FSs). The FSs include the novel topology of the integrated unit of ES with electric vehicles (EVs) parking (IUEE) and incentive-based demand response program (DRP). The proposed FPM model is formulated as an optimization problem that minimizes the difference between the expected energy cost and the expected profit of FSs' flexibility subject to the AC optimal power flow (AC-OPF), RESs, FSs, and MG flexibility constraints. In...