Switching State-Feedback LPV Control with Uncertain Scheduling Parameters

This paper presents a new method to design Robust Switching State-Feedback Gain-Scheduling (RSSFGS) controllers for Linear Parameter Varying (LPV) systems with uncertain scheduling parameters. The domain of scheduling parameters are divided into several overlapped subregions to undergo hysteresis switching among a family of simultaneously designed LPV controllers over the corresponding subregion with the guaranteed H-infinity performance. The synthesis conditions are given in terms of Parameterized Linear Matrix Inequalities that guarantee both stability and performance at each subregion and associated switching surfaces. The switching stability is ensured by descent parameter-dependent Lyapunov function on switching surfaces. By solving the optimization problem, RSSFGS controller can be obtained for each subregion. A numerical example is given to illustrate the effectiveness of the proposed approach over the non-switching controllers

LPV Modeling and Control for Active Flutter Suppression of a Smart Airfoil

In this paper, a novel technique of linear parameter varying (LPV) modeling and control of a smart airfoil for active flutter suppression is proposed, where the smart airfoil has a groove along its chord and contains a moving mass that is used to control the airfoil pitching and plunging motions. The new LPV modeling technique is proposed that uses mass position as a scheduling parameter to describe the physical constraint of the moving mass, in addition the hard constraint at the boundaries is realized by proper selection of the parameter varying function. Therefore, the position of the moving mass and the free stream airspeed are considered the scheduling parameters in the study. A state-feedback based LPV gain-scheduling controller with guaranteed H infinity performance is presented by utilizing the dynamics of the moving mass as scheduling parameter at a given airspeed. The numerical simulations demonstrate the effectiveness of the proposed LPV control architecture by significantly improving the performance while reducing the control effort

Magnetic and microstructural properties of single crystal terfenol-D

SIGLEAvailable from British Library Document Supply Centre- DSC:DX175955 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Synthesis Conditions for LPV Controller with Input Covariance Constraints

In this paper, novel synthesis conditions for state-feedback Linear Parameter Varying (LPV) controller with Input Covariance Constraints (ICC) are developed. The synthesis conditions achieve the following design requirements 1) some constraints need to be satisfied on the control energy and 2) optimizing the performance outputs for the entire parameter space of the LPV system. These conditions are formulated as convex optimization problem with Parameterized Linear Matrix Inequalities (PLMIs) constraints. The effectiveness of the proposed approach is illustrated through numerical examples

Some blood parameters study in albino female mice orally given crude aqueous soy bean (Glycine max) seeds extract

The possible effect of the crude aqueous extract of soy bean seeds on some blood parameters (total count of red blood cells, white blood cell , (total and differential) blood platelates, packed cell volume and concentration of blood hemoglobin) was studied in 20 albino female mice which were allocated in four experimental groups (5 mice/group). The first group was orally treated with distilled water (control group) while the second, third and fourth group were given a concentration of 4%, 6% and 8% of the extract, respectively. At the end of the daily gavaging, which lasted for 4 weeks, the animals were killed, after recording their life body weight, and blood samples were collected from each mice to study the effect of the extract on the above mentioned parameters. Some of the active ingredients in the soy bean seeds extract were analytically tested. This test showed that the extract contained flavonoids and saponins. The effect of the extract on the studied blood parameters is reflected by the following results: 1) Significant (