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Energy harvesting from plate using magnetic shape memory alloys
, Article Proceedings of the 6th RSI International Conference on Robotics and Mechatronics, IcRoM 2018, 23 October 2018 through 25 October 2018 ; 2019 , Pages 229-235 ; 9781728101279 (ISBN) ; Naderi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Ferromagnetic shape memory alloys (FSMA) are new class of smart material and have been investigated for sensor and actuator and energy harvester applications.this paper presents the basis for a novel pressure sensor based on ferromagnetic shape memory alloys. Underlying mechanism for sensing applications is martensitic reorientation accompanied by a chang of magnetization of plate. When this alloy, is exposed in an external magnetic field or stress, has change of magnetization in result.the change in the magnetization of the alloy in accordance with the Faraday induction law, in the wires of the coil leads to the induction voltage. In this paper, a phenomenological constitutive structural...
Modeling of magnetic shape memory alloy plates for pressure sensor application
, Article Journal of Intelligent Material Systems and Structures ; 2020 ; Naderi, H ; Sharif University of Technology
SAGE Publications Ltd
2020
Abstract
This article investigates the basis for pressure sensor application based on the magnetic shape memory effect in membranes. Von Karmans nonlinear terms are considered in strain–displacement relationships of thin films, and a new method is presented for solution of large deflections of thin films with arbitrary boundary condition. In this study, the equations of motion of magnetic shape memory alloys are extended. In pressurized membranes, the complex distribution of mechanical stress can cause the martensitic reorientation, which is the underlying mechanism for sensing applications in magnetic shape memory alloys. To examine the obtained model, the governing equations of magnetic shape...
Modeling of magnetic shape memory alloy plates for pressure sensor application
, Article Journal of Intelligent Material Systems and Structures ; Volume 32, Issue 2 , 2021 , Pages 196-207 ; 1045389X (ISSN) ; Naderi, H ; Sharif University of Technology
SAGE Publications Ltd
2021
Abstract
This article investigates the basis for pressure sensor application based on the magnetic shape memory effect in membranes. Von Karmans nonlinear terms are considered in strain–displacement relationships of thin films, and a new method is presented for solution of large deflections of thin films with arbitrary boundary condition. In this study, the equations of motion of magnetic shape memory alloys are extended. In pressurized membranes, the complex distribution of mechanical stress can cause the martensitic reorientation, which is the underlying mechanism for sensing applications in magnetic shape memory alloys. To examine the obtained model, the governing equations of magnetic shape...
Control of car-like (wheeled) multi robots for following and hunting a moving target
, Article Scientia Iranica ; Volume 18, Issue 4 B , August , 2011 , Pages 950-965 ; 10263098 (ISSN) ; Kouhi, H ; Salarieh, H ; Sharif University of Technology
2011
Abstract
The main purpose of this paper is to design a decentralized controller for some car-like (wheeled) multi robots to follow and hunt a moving target. Considering geometric dimensions, mass and moment of inertia, robots are very similar to actual cars in which the outputs of the controller are steering and driving wheel torques. All robots are equipped with range and bearing sensors along with antenna, to communicate radio wave signals. A Kalman filter is implemented to estimate relative position, state variables of the target and state variables of other robots. The controller is designed to carry out the group maneuver of the system, based on the system dynamics analysis of inertial agents,...
Modeling of a nonlinear Euler-Bernoulli flexible beam actuated by two active shape memory alloy actuators
, Article Journal of Intelligent Material Systems and Structures ; Volume 22, Issue 11 , 2011 , Pages 1249-1268 ; 1045389X (ISSN) ; Salehi, H ; Sayyaadi, H ; Sharif University of Technology
2011
Abstract
There are two different ways of using shape memory alloy (SMA) wire as an actuator for shape control of flexible structures: it can be either embedded within the composite laminate or externally attached to the structure. As the actuator can be placed at different offset distances from the beam, external actuators produce more bending moment and, consequently, considerabnle shape changes with the same magnitude of actuation force compared with the embedded type. Such a configuration also provides faster heat transfer rate owing to convection, which is very important in shape control applications that require a highfrequency response of SMA actuators. Although combination and physics-based...
Prosthetic knee using of hybrid concept of magnetorheological brake with a T-shaped drum
, Article 2015 IEEE International Conference on Mechatronics and Automation, ICMA 2015, 2 August 2015 through 5 August 2015 ; Aug , 2015 , Pages 721-726 ; 9781479970964 (ISBN) ; Zareh, S. H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
This paper focuses on developing a new configuration on magnetorheological (MR) brake damper as prosthetic knee. Knee uses magnetic fields to vary the viscosity of the MR fluid, and thereby its flexion resistance. Exerted transmissibility torque of the knee greatly depends on the magnetic field intensity in the MR fluid. In this study a rotary damper using MR fluid is addressed in which a single rotary disc will act as a brake while MR fluid is activated by magnetic field in different walking gait. The main objective of this study is to investigate a prosthetic knee with one activating rotary disc to accomplish necessary braking torque in walking gait via implementing of Newton's equation of...
A new configuration in a prosthetic knee using of hybrid concept of an MR brake with a T-Shaped drum incorporating an arc form surface
, Article Smart Structures and Systems ; Volume 17, Issue 2 , 2016 , Pages 275-296 ; 17381584 (ISSN) ; Zareh, S. H ; Sharif University of Technology
Techno Press
2016
Abstract
This paper focuses on developing a new configuration on magnetorheological (MR) brake damper as prosthetic knee. Prosthetic knee uses magnetic fields to vary the viscosity of the MR fluid, and thereby its flexion resistance. Exerted transmissibility torque of the knee greatly depends on the magnetic field intensity in the MR fluid. In this study a rotary damper using MR fluid is addressed in which a single rotary disc will act as a brake while MR fluid is activated by magnetic field in different walking gait. The main objective of this study is to investigate a prosthetic knee with one activating rotary disc to accomplish necessary braking torque in walking gait via T-shaped drum with arc...
Intelligent control of an MR prosthesis knee using of a hybrid self-organizing fuzzy controller and multidimensional wavelet NN
, Article Journal of Mechanical Science and Technology ; Volume 31, Issue 7 , 2017 , Pages 3509-3518 ; 1738494X (ISSN) ; Zareh, S. H ; Sharif University of Technology
Korean Society of Mechanical Engineers
2017
Abstract
A Magneto rheological (MR) rotary brake as a prosthesis knee is addressed here. To the gait of the amputee, the brake, automatically adapts knee damping coefficient using only local sensing of the knee torque and position. It is difficult to design a model-based controller, since the MR knee system has nonlinear and very complicated governing mathematical equations. Hence, a Hybrid self-organizing fuzzy controller and multidimensional wavelet neural network (HSFCMWNN) is proposed here to control the knee damping coefficient using of the inverse dynamics of the MR rotary damper. A Self-organizing fuzzy controller (SOFC) is also proposed and during the control process, the SOFC continually...
Challenges in calculation of critical buckling load of tubular members of jacket platforms in finite element modeling
, Article Journal of Marine Science and Technology (Japan) ; 2019 ; 09484280 (ISSN) ; Erfani, M. H ; Sayyaadi, H ; Sharif University of Technology
Springer Tokyo
2019
Abstract
Accurate estimation of the capacity curve of offshore jacket structures to achieve performance levels and ductility is of great importance. Proper modeling of compressive members to correctly investigate global and local buckling is crucial in estimation of the capacity curve. Buckling modes and deformations due to local buckling can be considered, if the compressive braces are modeled by shell or solid elements. The purpose of this paper is to achieve the correct compressive behavior of braces with solid type elements and investigate the effects of five different parameters such as D/t, L/D, mesh size, mesh size ratio, and imperfections. ABAQUS FE software is used for this purpose. The...
Challenges in calculation of critical buckling load of tubular members of jacket platforms in finite element modeling
, Article Journal of Marine Science and Technology (Japan) ; 2019 ; 09484280 (ISSN) ; Erfani, M. H ; Sayyaadi, H ; Sharif University of Technology
Springer Tokyo
2019
Abstract
Accurate estimation of the capacity curve of offshore jacket structures to achieve performance levels and ductility is of great importance. Proper modeling of compressive members to correctly investigate global and local buckling is crucial in estimation of the capacity curve. Buckling modes and deformations due to local buckling can be considered, if the compressive braces are modeled by shell or solid elements. The purpose of this paper is to achieve the correct compressive behavior of braces with solid type elements and investigate the effects of five different parameters such as D/t, L/D, mesh size, mesh size ratio, and imperfections. ABAQUS FE software is used for this purpose. The...
Challenges in calculation of critical buckling load of tubular members of jacket platforms in finite element modeling
, Article Journal of Marine Science and Technology (Japan) ; Volume 25, Issue 3 , 2020 , Pages 866-886 ; Erfani, M. H ; Sayyaadi, H ; Sharif University of Technology
Springer
2020
Abstract
Accurate estimation of the capacity curve of offshore jacket structures to achieve performance levels and ductility is of great importance. Proper modeling of compressive members to correctly investigate global and local buckling is crucial in estimation of the capacity curve. Buckling modes and deformations due to local buckling can be considered, if the compressive braces are modeled by shell or solid elements. The purpose of this paper is to achieve the correct compressive behavior of braces with solid type elements and investigate the effects of five different parameters such as D/t, L/D, mesh size, mesh size ratio, and imperfections. ABAQUS FE software is used for this purpose. The...
A comparative analysis of some one-dimensional shape memory alloy constitutive models based on experimental tests
, Article Scientia Iranica ; Volume 19, Issue 2 , Volume 19, Issue 2 , 2012 , Pages 249-257 ; 10263098 (ISSN) ; Zakerzadeh, M. R ; Salehi, H ; Sharif University of Technology
2012
Abstract
Recently, Shape Memory Alloys (SMAs) have been receiving more attention and further study, due to their ability to develop extremely large, recoverable strains and great forces. In this paper, three major models of SMA behavior, used in the literature, for studying the static performance of SMA components attributed to Tanaka, Liang and Rogers, and Brinson, have been analyzed and compared. The major differences and similarities between these models have also been emphasized and presented in this paper, based on the experimental data of the shape memory and superelastic behavior of an SMA wire. It is shown that these models all agree well in their prediction of the superelastic behavior of...
Fuzzy sliding mode control of multi-agent systems using artificial potentials
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010, Vancouver, BC ; Volume 8, Issue PARTS A AND B , 2010 , Pages 901-909 ; 9780791844458 (ISBN) ; Mortazavi, J ; Alasty, A ; Sayyaadi, H ; Sharif University of Technology
2010
Abstract
In this paper a fuzzy control strategy of autonomous multiagent systems is presented. The main purpose is to obtain an improvement on the results of designed sliding mode controllers in previous articles using supervisory fuzzy controller. Similarly, a quasi-static swarm model in ndimensional space is introduced wherein the inter-individual interactions are based on artificial potential functions; and the motions of members are in direction with the negative gradient of the combined potentials which are the result of a balance between inter-individual interactions and the simultaneous interactions of the swarm members with their environment. Then a general model for vehicle dynamics of each...
Hydrodynamic analysis of trimaran vessels
, Article Polish Maritime Research ; Volume 15, Issue 1 , June , 2008 , Pages 11-18 ; 12332585 (ISSN) ; Jahanbakhsh, E ; Seif, M ; Sayyaadi, H ; Sharif University of Technology
2008
Abstract
Trimaran vessels are developed for different applications and hydrodynamic behavior of such vessels is different than usual mono-hulls. In this paper hydrodynamic resistance and maneuvering of a trimaran with Wigley body form are investigated. The effects of outriggers position in four different longitudinal and two transverse locations are studied. For hydrodynamic simulations a CFD code has been developed and used. This code is capable for simulating three dimensional, time dependent, two phases, viscous flow coupled with rigid body motion. Formulation and solution algorithm are described in detail. Different case studies have been performance and numerical results have shown good...
Minimizing the levelized cost of energy in an offshore wind farm with non-homogeneous turbines through layout optimization
, Article Ocean Engineering ; Volume 249 , 2022 ; 00298018 (ISSN) ; Khorasanchi, M ; Sayyaadi, H ; Sadollah, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Minimum cost of energy is the main goal of a wind farm layout optimization. This is achieved by maximizing the total energy while minimizing the total costs of the farm. In this study, two sizes of commercial turbines were considered to investigate the effect of a non-homogenous farm on the layout optimization process. A cost model consisting of turbines, cable, transformers, foundation, and service vehicle routes was developed. Using Genetic Algorithm and Artificial Neural Network, first the superiority of the new algorithm in turbines and cable layout was verified versus previous studies. Next, two cases were investigated, i.e. (1) a farm populated with identical turbines and (2) a farm...
Modeling and parametric studies of magnetic shape memory alloy–based energy harvester
, Article Journal of Intelligent Material Systems and Structures ; Volume 29, Issue 4 , 2018 , Pages 563-573 ; 1045389X (ISSN) ; Rostami Najafabadi, H ; Askari Farsangi, M. A ; Sharif University of Technology
SAGE Publications Ltd
2018
Abstract
This article presents a model to simulate the behavior of a magnetic shape memory alloy while harvesting vibratory energy. In this type of energy harvester, magnetic shape memory alloy element is placed in the air gap of a ferromagnetic core which conducts the magnetic flux. Two apparent coils are wound around a ferromagnetic core: one to produce bias magnetic field by passing a rectified electric current and the other to serve as an energy pickup coil. Applying compressive time-variant strain field to magnetic shape memory alloy element changes its dimensions and magnetic properties as well. Presence of the bias magnetic field returns magnetic shape memory alloy element to its initial state...
Flexible formation of multiple car-like robots with respect to a dynamic environment
, Article Scientia Iranica ; Volume 23, Issue 4 , 2016 , Pages 1844-1855 ; 10263098 (ISSN) ; Sharif University of Technology
Sharif University of Technology
2016
Abstract
This paper attempts to give a perspective on decentralized formation control of multiple car-like mobile robots using local information and formation changes in a dynamic environment having several obstacles. In addition, for every mobile robot, it takes physical dimensions, mass, moment of inertia, movement constraints, and saturation of actuators into account. This study makes use of Input/Output Feedback Linearization Method to control each robot. Hence, hierarchical leader-follower based algorithm is employed to control the group formation. To avoid collision between robots and obstacles, and of robots with each other, local artificial potential fields are addressed. The group can change...
Hysteresis nonlinearity identification using new Preisach model-based artificial neural network approach
, Article Journal of Applied Mathematics ; Volume 2011 , 2011 ; 1110757X (ISSN) ; Firouzi, M ; Sayyaadi, H ; Shouraki, S. B ; Sharif University of Technology
2011
Abstract
Preisach model is a well-known hysteresis identification method in which the hysteresis is modeled by linear combination of hysteresis operators. Although Preisach model describes the main features of system with hysteresis behavior, due to its rigorous numerical nature, it is not convenient to use in real-time control applications. Here a novel neural network approach based on the Preisach model is addressed, provides accurate hysteresis nonlinearity modeling in comparison with the classical Preisach model and can be used for many applications such as hysteresis nonlinearity control and identification in SMA and Piezo actuators and performance evaluation in some physical systems such as...
Hysteresis identification of shape memory alloy actuators using a novel artificial neural network based Presiach model
, Article ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2010, 28 September 2010 through 1 October 2010 ; Volume 1 , 2010 , Pages 653-660 ; 9780791844151 (ISBN) ; Firouzi, M ; Sayyaadi, H ; Bagheri Shouraki, S ; Sharif University of Technology
2010
Abstract
In systems with hysteresis behavior like Shape Memory Alloy (SMA) actuators and Piezo actuators, an accurate modeling of hysteresis behavior either for performance evaluation and identification or controller design is essentially needed. One of the most interesting hysteresis none-linearity identification methods is Preisach model which the hysteresis is modeled by linear combination of hysteresis operators. In spite of good ability of the Preisach model to extract the main features of system with hysteresis behavior, due to its numerical nature, it is not convenient to use in real time control applications. In this paper a novel artificial neural network (ANN) approach based on the Preisach...
Spatial Swarm Robotics and Decentralized and Scalable Control Mission
, M.Sc. Thesis Sharif University of Technology ; Sayyaadi, Hassan (Supervisor)
Abstract
Swarm robots have been interested by researchers in recent years. The most important reason of this attention is the abilities of these systems for doing some works that a single robot can’t do them alone. The goal of this article is formation control of a group of flying robots with nonholonomic dynamics. The agents are considered helicopters with dimension, mass and moment of inertia. Firstly, the dynamics equation of helicopter will be derived as for Newton-Euler method. Next, input-output equations will be derived and controller will be designed by using sliding mode method. Main rotor and tail rotor thrusts, roll and pitch torques of main rotor are the system inputs. The control method...