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Two novel approaches of adaptive finite-time sliding mode control for a class of single-input multiple-output uncertain nonlinear systems

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IET Cyber-Systems and Robotics 2021年第2期3卷 173-183页

作者： Pooyan alinaghi Hosseinabadi ali soltani sharif abadi Saad Mekhilef Hemanshu Roy Pota Power Electronics and Renewable Energy Research Laboratory(PEARL) Department of Electrical EngineeringUniversity of MalayaFaculty of EngineeringKuala LumpurMalaysia Department of Electrical Engineering Yazd UniversityFaculty of EngineeringYazdIran School of Software and Electrical Engineering Swinburne University of TechnologyVictoriaAustralia School of Engineering and Information Technology The University of New South WalesCanberraAustralia

Some systems,in spite of having multiple outputs,have only one control input,which makes their control a *** novel controllers are proposed that utilise an adaptive finite-time sliding mode control(AFSMC)scheme for a class of single-input multiple-output(SIMO)nonlinear systems in the presence of unknown mismatched *** alleviate the inherent chattering phenomenon of sliding mode control,new forms of the two designed controllers are suggested by using new sliding *** only can the proposed AFSMC scheme stabilise the system in a finite time,but also it can provide estimated data of the uncertainty upper bound in the *** stability theory is used to obtain finite-time stability analysis of the closed-loop ***,simulation results are carried out in Simulink/MATLAB for a four-dimensional autonomous hyper-chaotic system with mismatched uncertainties as an example of SIMO uncertain nonlinear systems to reveal the effectiveness of the proposed controllers.

关键词： finite nonlinear stability

Control and Treatment of Bone Cancer: A Novel Theoretical Study

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Journal of Electronic & Information Systems 2023年第2期5卷 35-44页

作者： ali soltani sharif abadi Mansour Rafeeyan Vahid Abootalebi Institute of Automatic Control and Robotics Faculty of MechatronicsWarsaw University of TechnologyWarsaw00-664Poland Institute of Electronic Systems Faculty of Electronics and Information TechnologyWarsaw University of TechnologyWarsaw00-664Poland Faculty of Mechanics Yazd UniversityYazd***Iran Faculty of Electrical Engineering Yazd UniversityYazd***Iran

The human body has symmetric *** paper uses control engineering concepts to design a suitable controller to synchronize two symmetric bones of the human body to control and treat bone cancer.A Nonsingular Terminal Sliding Mode Control(NTSMC)method will be employed to design the proposed control *** control inputs can be the chemical drugs that can be used to treat bone *** dynamical equations of bone cancer will be used to apply the designed control method and test *** testing the designed controller,Simulink/MATLAB software will be *** proposed controller is chattering-free,robust against uncertainties and external disturbances,and finite-time stable in the control engineering *** cancer will be treated for almost one year using the proposed control method.

关键词： Bone cancer Synchronization Finite-time stability Biomedical engineering

Modeling and control for cooperative transport of a slung fluid container using quadrotors

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Chinese Journal of Aeronautics 2018年第2期31卷 262-272页

作者： Hassan SAYYAADI ali soltani School of Mechanical Engineering Sharif University of Technology

In this paper, dynamic modeling and control problem for transfer of a sloshing liquid container suspended through rigid massless links from a team of quadrotors are investigated. By the proposed solution, pose of the slung container and fluid sloshing modes are stabilized appropriately. Dynamics of the container-liquid-quadrotors system is modeled by Euler-Lagrange *** slosh dynamics is included using multi-mass-spring model. According to derived model, a proper control law is designed for a system with three or more quadrotors. Implementing the proposed control law, quadrotors can control pose of the container, directions of the links and liquid sloshing modes simultaneously. Stability of closed loop system of tracking errors and sloshing modes are demonstrated using a theory of singularly perturbed systems and Lyapunov stability theorem. Also, the capability of the proposed feedback control laws in solving a formerly organized transport problem of a liquid filled container has been demonstrated in simulations. Moreover, priority of the proposed control scheme to an existing slung load controller in the literature is demonstrated.

关键词： Cooperative transport Dynamic modeling Liquid sloshing Lyapunov stability Pose control Quadrotors Slung load

Experimental investigation of shock-buffet criteria on a pitching airfoil

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Chinese Journal of Aeronautics 2022年第7期35卷 179-191页

作者： Mehran MASDARI Aghil ZEINALZADEH Mohammad ali ABDI Mohammad Reza soltani Faculty of New Sciences and Technologies University of TehranTehran ***Iran Department of Aerospace Engineering Sharif University of TechnologyTehran 11365-11155Iran Department of Aeronautical and Astronomical Engineering University of WashingtonSeattleWAUSA

An experimental investigation of the shock-buffet phenomenon subject to unsteady pitching supercritical airfoil around its quarter chord has been conducted in a transonic wind *** model was equipped with pressure taps connected to the fast response *** were conducted at different free-stream Mach number from 0.61 *** principle goal of this investigation was to experimentally discuss the shock-buffet criterion over a SC(2)-0410 supercritical pitching related to the hysteresis loops of total drag and trailing edge pressure,the behaviour of the shock wave foot location,the pressure distribution over the upper surface,and by implementing the wavelet analysis of the normal *** ensure capturing the buffet phenomenon by utilizing these criteria,a pressure port has been drilled exactly at the trailing edge of the airfoil where its output was used to detect the buffet phenomenon for different *** representation of the flow using the shadow graph flow visualization technique for different test cases is further used to illustrate the unsteady shock wave motion.A comparative analysis of experimental measurements shows that the conducted criteria confirm each other when the buffet phenomenon occurs at the position of the oscillating cycle.

关键词： Airfoil Buffeting Experimental analysis Hysteresis loops Pitching motion Shock wave Wavelet analysis

Impact of reduced frequency on the time lag in pressure distribution over a supercritical airfoil in a pitch-pause-return motion

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Chinese Journal of Aeronautics 2019年第2期32卷 243-252页

作者： Haghighat Z.ESLAMI ali R.DAVARI M.R.soltani Aerospace Division Department of Engineering Science and Research Branch Islamic Azad University Department of Aerospace Engineering Sharif University of Technology

Effects of reduced frequency, stop angle, and pause duration have been studied on a thin supercritical airfoil undergoing a pitch-pause-return motion, which is one of the classic maneuvers introduced by the AIAA Fluid Dynamics Technical Committee. Experiments were conducted in a low-speed wind tunnel at both a constant mean angle of attack and an oscillation amplitude with a reduced frequency ranging from 0.01 to 0.12. The desired stop angles of the airfoil were set to occur during the upstroke motion. The unsteady pressure distribution on the airfoil was measured for below, near, and beyond static stall conditions. Results showed that the reduced frequency and stop angle were the dominant contributors to the time lag in the flowfield. For stop angles in both belowand post-stall regions, the time for the flowfield to reach its steady state conditions, known as the time lag, decreased as the reduced frequency was increased. However, in the static-stall region and for a certain value of reduced frequency, a resonance phenomenon was observed, and a minimum time lag was achieved. The pressure distribution in this condition was shown to be highly influenced by this phenomenon.

关键词： Dynamic stall Pitch pause return motion Reduced frequency Static stall Time lag

Effects of Mach numbers on Magnus induced surface pressure

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Chinese Journal of Aeronautics 2020年第12期33卷 3058-3072页

作者： F.ASKARY M.R.soltani Department of Aerospace Engineering Sharif UniversityTehran P.O.B ***Iran Department of Aeronautics and Astronautics University of WashingtonSeattle BOX 352400USA

Experimental and numerical methods were used to investigate the Magnus phenomena over a spinning *** pressure force acting on the surface of a spinning projectile was measured for various cases by employing a relatively novel experimental technique.A set of miniature pressure sensors along with a data acquisition board,battery and storage memory were placed inside a spinning model and the surface pressure were obtained through a remotely controlled *** pressures of the model for both rotational and static conditions were obtained at two different free stream Mach numbers of 0.4 and 0.8 and at different angles of *** results showed the ability of this new test method to measure the very small Magnus force via surface pressures over the *** results provide a deep insight into the flow structure and illustrate changes in the cross-flow separation locations as a result of *** results were obtained by the numerical simulations and were compared with the experimental data.

关键词： Magnus effect Spinning projectile Surface pressure Wind tunnel

Effect of an end plate on surface pressure distributions of two swept wings

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Chinese Journal of Aeronautics 2017年第5期30卷 1631-1643页

作者： Mohammad Reza soltani Mehran MASDARI Mohammad Rasoul TIRANDAZ Department of Aerospace Engineering Sharif University of Technology Tehran 19166Iran Faculty of New Sciences and Technologies University of Tehran Tehran Iran

A series of wind tunnel tests was conducted to examine how an end plate affects the pressure distributions of two wings with leading edge（LE） sweep angles of 23° and 40°. All the experiments were carried out at a midchord Reynolds number of 8×10～5, covering an angle of attack（AOA） range from -2° to 14°. Static pressure distribution measurements were acquired over the upper surfaces of the wings along three chordwise rows and one spanwise direction at the wing quarter-chord line. The results of the tests confirm that at a particular AOA, increasing the sweep angle causes a noticeable decrease in the upper-surface suction pressure. Furthermore, as the sweep angle increases, the development of a laminar separation bubble near the LEs of the wings takes place at higher AOAs. On the other hand, spanwise pressure measurements show that increasing the wing sweep angle results in forming a stronger vortex on the quarter-chord line which has lower sensitivity to AOA variation and remains substantially attached to the wing surface for higher AOAs than that can be achieved in the case of a lower sweep angle. In addition, data obtained indicate that installing an end plate further reinforces the spanwise flow over the wing surface, thus affecting the pressure distribution.

关键词： Chordwise Flow field Pressure distribution Swept wing Wind tunnel

Experimental study of the boundary layer over an airfoil in plunging motion

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Acta Mechanica Sinica 2012年第2期28卷 372-384页

作者： F.Rasi Marzabadi M.R.soltani Aerospace Research Institute TehranIran Department of Aerospace Engineering Sharif University of TechnologyTehranIran

This is an experimental study on the bound- ary layer over an airfoil under steady and unsteady conditions. It specifically deals with the effect of plunging oscil- lation on the laminar/turbulent characteristics of the bound- ary layer. The wind tunnel measurements involved surface- mounted hot-film sensors and boundary-layer rake. The ex- periments were conducted at Reynolds numbers of 0.42 x 106 to 0.84 X l06 and the reduced frequency was varied from 0.01 to 0.11. The results of the quasi-wall-shear stress as well as the boundary layer velocity profiles provided impor- tant information about the state of the boundary layer over the suction surface of the airfoil in both static and dynamic cases. For the static tests, boundary layer transition occurred through a laminar separation bubble. By increasing the an- gle of attack, disturbances and the transition location moved toward the leading edge. For the dynamic tests, earlier transi- tion occurred with increasing rather than decreasing effective angle of attack. The mean angle of attack and the oscillating parameters significantly affected the state of the boundary layer. By increasing the reduced frequency, the boundary layer transition was promoted to the upstroke portion of the equivalent angle of attack, but the quasi skin friction coeffi- cient was decreased.

关键词： Boundary layer Unsteady - Plunging Wind tunnel Airfoil

Experimental study on correlation between turbulence and sound in a subsonic wind tunnel

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Acta Mechanica Sinica 2010年第4期26卷 531-539页

作者： M.D.Manshadi K.Ghorbanian M.R.soltani Department of Aerospace Engineering Sharif University of Technology

In this paper, the effects of turbulence on sound generation and velocity fluctuations due to pressure waves in a large subsonic wind tunnel are studied. A trip strip located at different positions in the contraction part or at one position in the diffuser of a large wind tunnel is used to investigate the aforementioned phenomenon, and the results indicate that the trip strip has significant effects on sound reduction. The lowest turbulence intensity and sound are obtained from a trip strip with a diameter of 0.91 mm located either at X/L = 0.79 or at X/L = 0.115 in the wide portion of the contraction. Furthermore, the effect of monopole, dipole and quadrupole sources of aerodynamic noise at different velocities is investigated, and it is demonstrated that the contribution of the monopole is dominant, while the shares due to the dipole and quadrupole remain less important. In addition, it is found that the sound waves have a modest impact on the measured longitudinal turbulence and are generated essentially by eddies.

关键词： Wind tunnel. Turbulence Sound Quadrupole term - Correlation