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    Dynamic manipulation of objects using multiple manipulators

    , Article ASME International Mechanical Engineering Congress and Exposition, IMECE 2007, Seattle, WA, 11 November 2007 through 15 November 2007 ; Volume 9 PART B , 2008 , Pages 1201-1208 ; 0791843033 (ISBN); 9780791843031 (ISBN) Beigzadeh, B ; Meghdari, A ; Beigzadeh, Y ; Sharif University of Technology
    2008
    Abstract
    In this study, we explore the possibility of dynamic object manipulation of objects using a series of manipulators. Here, two three-active-link manipulators have been considered and the generality of the idea to a series of manipulator is developed easily. So without any gripper, and in an unstable grasp manner, we try to throw an object by a manipulator and catch It with another. Also we can consider the impacts generated in the moment of throwing and catching objects, as some disturbance and therefore we damp it. Finally we deal with the whole manipulation process as a system with some noise and disturbance and try to demonstrate its stability. All results have been validated with the aid... 

    Passive dynamic object manipulation: preliminary definition and examples

    , Article Acta Automatica Sinica ; Volume 36, Issue 12, December 2010, Pages 1711–1719 Beigzadeh, B ; Meghdari, A. (Ali) ; Sohrabpour, S ; Sharif University of Technology
    Abstract
    In this work, we introduce a category of dynamic manipulation processes, namely passive dynamic object manipulation, according to which an object is manipulated passively. Specifically, we study passive dynamic manipulation here. We define the main concept, discuss the challenges, and talk about the future directions. Like other passive robotic systems, there are no actuators in these systems. The object follows a path and travels along it under the effect of its own weight, as well as the interaction force applied by each manipulator on it. We select some simple examples to show the concept. For each example, dynamic equations of motion are derived and the stability of the process is taken... 

    Optimal task-space manipulability of hybrid 4-DOF dual-arm cam-lock manipulators

    , Article Proceeding of the 5th International Symposium on Mechatronics and its Applications, ISMA 2008, 27 May 2008 through 29 May 2008, Amman ; 2008 ; 9781424420346 (ISBN) Ghaemi Osgouie, K ; Meghdari, A ; Sohrabpour, S ; Sharif University of Technology
    2008
    Abstract
    The Dual-Arm Cam-Lock robot is a reconfigurable manipulator formed by two parallel cooperative arms. Based on the application, these arms may loose some degrees of freedom by locking into each other. However, they are considered as redundant arms when operating without any locked joints/links. In this paper, a method is introduced to find the optimal configuration of this manipulator. The objective is to find the configuration in which maximum cooperative force is exerted to an object in a specific direction. The dynamics of the robot is parametrically formulated for different configurations, and by considering the geometrical constraints optimization is performed using fine-mesh and genetic... 

    Manipulability analysis for gimbal driven robotic arms

    , Article 2009 IEEE International Conference on Robotics and Biomimetics, ROBIO 2009, 19 December 2009 through 23 December 2009 ; 2009 , Pages 1039-1044 ; 9781424447756 (ISBN) Mohammadi, F ; Hemmatian, I ; Ghaem Osgouie, K ; Sharif University of Technology
    Abstract
    Gimbal transmissions are non-linear direct transmissions and can be used in robotic arms replacing the traditional revolute joints. To investigate manipulability of robotic manipulators, the classical criterion of Manipulability Ellipsoid has been formulated. Thus by keeping a constant norm for robot joint torques vector, the effects of replacing some traditional revolute joints in robotic arms with Gimbal transmissions, have been analyzed. The results show that the magnitude of the maximum force applicable when employing Gimbal transmission can be considerably larger. Also, the joint angles in which this maximum occurs, can be adjusted, thanks to the behavior of Gimbal transmission. Two... 

    Passive dynamic object manipulation: A framework for passive walking systems

    , Article Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics ; Volume 227, Issue 2 , 2013 , Pages 185-198 ; 14644193 (ISSN) Beigzadeh, B ; Meghdari, A ; Sohrabpour, S ; Sharif University of Technology
    2013
    Abstract
    In this study, we deal with passive dynamic object manipulation. During passive dynamic object manipulation, a passive object is manipulated using passive manipulators. Like other passive robotic systems, there are no actuators in these systems. The object follows a path and travels along it under the effect of its own weight, as well as, the interaction force applied by each manipulator on it. The objects are not necessarily rigid, but we manipulate passive multibody objects as well as rigid ones. Thus, for a passive walking system, we assume that the passive walker is a multibody object and is manipulated by the ground (zero degree-of-freedom manipulator). As an example, we show that a... 

    Beam manipulation by hybrid plasmonic-dielectric metasurfaces

    , Article Plasmonics ; 2019 ; 15571955 (ISSN) Arik, K ; Hemmatyar, O ; Kavehvash, Z ; Sharif University of Technology
    Springer  2019
    Abstract
    A hybrid plasmonic-dielectric metasurface is proposed in order to manipulate beam propagation in desired manners. The metasurface is composed of patterned hybrid graphene-silicon nano-disks deposited on a low-index substrate, namely silica. It is shown that the proposed hybrid metasurface simultaneously benefits from the advantages of graphene-based metasurfaces and dielectric ones. Specially, we show that the proposed hybrid metasurface not only provides reconfigurability, just like previously proposed graphene-based metasurfaces, but also similar to dielectric metasurfaces, is of low loss and CMOS-compatible. Such exceptional features give the metasurface exceptional potentials to realize... 

    Beam manipulation by hybrid plasmonic-dielectric metasurfaces

    , Article Plasmonics ; Volume 15, Issue 3 , 2020 , Pages 639-645 Arik, K ; Hemmatyar, O ; Kavehvash, Z ; Sharif University of Technology
    Springer  2020
    Abstract
    A hybrid plasmonic-dielectric metasurface is proposed in order to manipulate beam propagation in desired manners. The metasurface is composed of patterned hybrid graphene-silicon nano-disks deposited on a low-index substrate, namely silica. It is shown that the proposed hybrid metasurface simultaneously benefits from the advantages of graphene-based metasurfaces and dielectric ones. Specially, we show that the proposed hybrid metasurface not only provides reconfigurability, just like previously proposed graphene-based metasurfaces, but also similar to dielectric metasurfaces, is of low loss and CMOS-compatible. Such exceptional features give the metasurface exceptional potentials to realize... 

    An articulated body algorithm for modelling and simulation of an underwater vehicle equipped with manipulator arm

    , Article 2003 ASME Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Chicago, IL, 2 September 2003 through 6 September 2003 ; Volume 2 B , 2003 , Pages 1259-1270 Meghdari, A ; Vossoughi, G. R ; Hosseini, M. A ; Sharif University of Technology
    American Society of Mechanical Engineers  2003
    Abstract
    In this paper, an efficient dynamic simulation algorithm is developed for an Unmanned Underwater Vehicle (UUV) with a N degrees of freedom manipulator. In addition to the effects of mobile base, the various hydrodynamic forces exerted on these systems in an underwater environment are also incorporated into the simulation. The effects modeled in this work are added mass, viscous drag, fluid acceleration, and buoyancy forces. Also the dynamics of thrusters are developed, and an appropriate mapping matrix dependent on the position and orientation of the thrusters on the vehicle, is used to calculate resultant forces and moments of the thrusters on the center of gravity of the vehicle. It should... 

    Dynamic modeling and analysis of a two d.o.f. mobile manipulator

    , Article Robotica ; Volume 19, Issue 2 , 2001 , Pages 177-185 ; 02635747 (ISSN) Naderi, D ; Meghdari, A ; Durali, M ; Sharif University of Technology
    2001
    Abstract
    This paper presents the kinematic and dynamic modeling of a two degrees of freedom manipulator attached to a vehicle with a two degrees of freedom suspension system. The vehicle is considered to move with a constant linear speed over an irregular ground-surface while the end-effector tracks a desired trajectory in a fixed reference frame. In addition, the effects of highly coupled dynamic interaction between the manipulator and vehicle (including the suspension system's effects) have been studied. Finally, simulation results for the end-effector's straight-line trajectory are presented to illustrate these effects  

    Optimization of kinematic redundancy and workspace analysis of a dual-arm cam-lock robot

    , Article Robotica ; 2014 ; ISSN: 02635747 Jouybari, B. R ; Osgouie, K. G ; Meghdari, A ; Sharif University of Technology
    Abstract
    In this paper, the problem of obtaining the optimal trajectory of a Dual-Arm Cam-Lock (DACL) robot is addressed. The DACL robot is a reconfigurable manipulator consisting of two cooperative arms, which may act separately. These may also be cam-locked in each other in some links and thus lose some degrees of freedom while gaining higher structural stiffness. This will also decrease their workspace volume. It is aimed to obtain the optimal configuration of the robot and the optimal joint trajectories to minimize the consumed energy for following a specific task space path. The Pontryagin's Minimum Principle is utilized with a shooting method to resolve kinematic redundancy. Numerical examples... 

    Manipulation of multibody active objects using simple passive manipulators

    , 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 597-603 ; 9780791844458 (ISBN) Beigzadeh, B ; Meghdari, A ; Sohrabpour, S ; Sharif University of Technology
    2010
    Abstract
    In this paper, we study passivity in dynamic manipulation of active objects. Active object is a concept covering a variety of objects, which are not rigid and need to be controlled during manipulation process. In this work, we use multi-link mechanisms with sufficient actuators to be controlled as object and a series of simple 1-DoF passive manipulators to perform such a process. Control of the object, dynamic and motion planning of the system, and stability in presence of impact are significant issues in this study  

    Control and manipulation of multibody objects

    , Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010, Istanbul ; Volume 3 , 2010 , Pages 579-584 ; 9780791849170 (ISBN) Beigzadeh, B ; Meghdari, A ; Sohrabpour, S ; Sharif University of Technology
    2010
    Abstract
    In this work, we study a kind of manipulation process during which we deal with active objects. An active object is a concept covering a variety of objects that are not rigid and need to be controlled during the manipulation process. Here, we use a multi-link mechanism with active motors (actuator) as the object and a series of simple planar manipulators to perform the manipulation process. Dynamic, control, motion planning, and stability at the presence of impact are the most important challenges in this work  

    Optimization, Fabrication and Utilization of a New Tendon Actuated Manipulator with Lockable Joints

    , M.Sc. Thesis Sharif University of Technology Shafaei, Mohsen (Author) ; Alasty, Aria (Supervisor) ; Salarieh, Hassan (Supervisor)
    Abstract
    Serpentine manipulators are a kind of hybrid manipulators that have a large number of joints and degrees of freedom. Due to their high flexibility, they have a great potential to work in constrained environment that filled with obstacles. One of the main problems of this type of manipulators is high weight and controlling difficulties. Many researches have been done to achieve lighter weight and simplify control methods of hyper-redundant manipulator. One way is putting the actuators in the base of the manipulator and transferring the actuator forces by cable. In this way, one cable and one actuator per controllable DOF is needed. Therefore, the weight and cost will increase dramatically... 

    Adaptive compensation of actuator dynamics in manipulators without joint torque measurement

    , Article Proceedings of the IEEE Conference on Decision and Contro ; December , 2013 , Pages 2294-2299 ; 01912216 (ISSN) ; 9781467357173 (ISBN) Kazemi, H ; Namvar, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2013
    Abstract
    Neglecting actuator dynamics in control of rigid manipulators can degrade performance and stability of the system. However, consideration of actuator dynamics usually requires measurement of joint torque or armature currents. In this paper, we present an adaptive controller for motion tracking of an n-DOF manipulator without using joint torque measurement. Semi-global convergence of motion and torque tracking errors to zero is proven. We show that the use of non-minimal representation of manipulator dynamics significantly simplifies its linear parametrization. Simulation example shows that avoiding joint torque measurement reduces system sensitivity to sensor failure and noise  

    Passive dynamic object manipulation: preliminary definition and examples

    , Article Zidonghua Xuebao/Acta Automatica Sinica ; Volume 36, Issue 12 , 2010 , Pages 1711-1719 ; 02544156 (ISSN) Beigzadeh, B ; Meghdari, A ; Sohrabpour, S ; Sharif University of Technology
    2010
    Abstract
    In this work, we introduce a category of dynamic manipulation processes, namely passive dynamic object manipulation, according to which an object is manipulated passively. Specifically, we study passive dynamic manipulation here. We define the main concept, discuss the challenges, and talk about the future directions. Like other passive robotic systems, there are no actuators in these systems. The object follows a path and travels along it under the effect of its own weight, as well as the interaction force applied by each manipulator on it. We select some simple examples to show the concept. For each example, dynamic equations of motion are derived and the stability of the process is taken... 

    Dealing with biped locomotion as a dynamic object manipulation problem: Manipulating of body using legs

    , Article ASME International Mechanical Engineering Congress and Exposition, IMECE 2007, Seattle, WA, 11 November 2007 through 15 November 2007 ; Volume 9 PART B , 2008 , Pages 1209-1216 ; 0791843033 (ISBN); 9780791843031 (ISBN) Beigzadeh, B ; Meghdari, A ; Beigzadeh, Y ; Sharif University of Technology
    2008
    Abstract
    In this paper, we try to show that it is possible to deal with biped locomotion as a dynamic object manipulation problem. We show that during locomotion, a biped locomotion can be seen as manipulating of upper part of biped robot using a leg, which now plays the role of a manipulator. So the whole locomotion process can be seen as a dynamic manipulation of an object (upper part of a biped robot) using a numerous series of manipulators each of which placed in a proper place where the object tends to land, so it catches the object and throws it to the next point which another manipulator waits for catching it. The authors in the previous works have explored the problem of dynamic manipulation... 

    Planning of dynamic compensation manipulator motions for stability enhancement of mobile manipulators by soft computing

    , Article 2006 ASME International Mechanical Engineering Congress and Exposition, IMECE2006, Chicago, IL, 5 November 2006 through 10 November 2006 ; 2006 ; 10716947 (ISSN); 0791837904 (ISBN); 9780791837900 (ISBN) Ghaffari, A ; Naderi, D ; Meghdari, A ; Eslami, S ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME)  2006
    Abstract
    Mobile manipulators are developed in order to execute separately in various regions where there is not possibility for human to appear there. Recently, the size of mobile manipulators has been decreased according to their given tasks. For such systems, the stability issue is very important. The robot system should be able to keep itself in an optimal situation. For reaching to this goal, one can use a redundant degree of freedom for the mobile manipulator such that this redundancy makes it possible to recover the system's stability by dynamic compensatory motion of manipulator when the system is unstable. In this paper, we present an algorithm which is fast enough to stabilize the mobile... 

    Two dimensional dynamic manipulation of a disc using two manipulators

    , Article 2006 IEEE International Conference on Mechatronics and Automation, ICMA 2006, Luoyang, 25 June 2006 through 28 June 2006 ; Volume 2006 , 2006 , Pages 1191-1196 ; 1424404665 (ISBN); 9781424404667 (ISBN) Beigzadeh, B ; Nili Ahmadabadi, M ; Meghdari, A ; Sharif University of Technology
    2006
    Abstract
    In this paper, we analyze a Dynamic Object Manipulation (DOM) problem; throwing upward and catching a disc using two planar manipulators. The manipulators control the disc xy position dynamically and use its angular movement as a free parameter. We use a simple model for the system. Each manipulator has three links and three active joints. In addition, the disc has considerable radius and mass. Therefore, we design a simple mechanism in the palm to damp a portion of the impact. © 2006 IEEE  

    PRI (Palm Rotation Indicator): a metric for postural stability in dynamic nonprehensile manipulation [electronic resource]

    , Article Journal of MECHANIKA ; 2012, Vol. 18, No. 4, pp. 461-466 Beigzadeh, B. (Borhan) ; Meghdar, Ali ; Sohrabpour, Saeed ; Sharif University of Technology
    Abstract
    In this study, we discuss the postural stability of a nonprehensile manipulation problem, which deals with multibody objects. As a metric for postural stability, we define PRI. Then, the system is posturally stable, if PRI is inside the convex hull of the object-manipulator contact surface. We then discuss that dynamic biped locomotion is a special case of dynamic nonprehensile manipulation in all aspects; we prove that ZMP (zero-moment point) and FRI (zoot rotation indicator) are special cases of PRI (palm rotation indicator). Simulations and experiments corresponding to simple examples support the results  

    A new obstacle avoidance method for discretely actuated hyper-redundant manipulators

    , Article Scientia Iranica ; Volume 19, Issue 4 , August , 2012 , Pages 1081-1091 ; 10263098 (ISSN) Motahari, A ; Zohoor, H ; Habibnejad Korayem, M ; Sharif University of Technology
    Elsevier  2012
    Abstract
    In this paper, a new method is proposed for solving the obstacle avoidance problem of discretely actuated hyper-redundant manipulators. In each step of the solution, the closest collision to the base is removed and then the configuration of the next part of the manipulator is modified without considering the obstacles. This process is performed repeatedly until no collision is found. The Suthakorn method is applied to solve the inverse kinematics problem. Two new ideas are proposed to reduce the errors of this method: the two-by-two searching method, and iterations. To verify the proposed method, some problems are solved numerically for 2D and 3D manipulators, each in two different obstacle...