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robotic-systems
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Role of laser sensor systems in automation and flexible manufacturing
, Article Robotics and Computer-Integrated Manufacturing ; Volume 19, Issue 1-2 , 2003 , Pages 201-210 ; 07365845 (ISSN) ; Sharif University of Technology
2003
Abstract
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...
Passive dynamic object manipulation: preliminary definition and examples
, Article Acta Automatica Sinica ; Volume 36, Issue 12, December 2010, Pages 1711–1719 ; 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...
Passive dynamic object manipulation: preliminary definition and examples
, Article Zidonghua Xuebao/Acta Automatica Sinica ; Volume 36, Issue 12 , 2010 , Pages 1711-1719 ; 02544156 (ISSN) ; 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...
Optimization of kinematic redundancy and workspace analysis of a dual-arm cam-lock robot
, Article Robotica ; 2014 ; ISSN: 02635747 ; 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...
Investigation on dynamic modeling of SURENA III humanoid robot with heel-off and heel-strike motions
, Article Iranian Journal of Science and Technology - Transactions of Mechanical Engineering ; Volume 41, Issue 1 , 2017 , Pages 9-23 ; 22286187 (ISSN) ; Yousefi Koma, A ; Khadiv, M ; Mansouri, S ; Sharif University of Technology
Shiraz University
2017
Abstract
The understudy SURENA III humanoid robot was designed and fabricated at the Center of Advanced Systems and Technologies (CAST) located in the Universityof Tehran. In this paper, a full dynamic model of SURENA III in different walking phases including heel-offand heel-strike motions is presented. To this end, first a trajectory planning method based on robot kinematics is introduced. Then, the multi-body dynamics of the robot links are calculated using Lagrange and Kane approaches which are then verified. In this model, the power transmissionsystem is considered to be ideal. Afterward, system identification routine is adopted to model the dynamic behavior of the power transmission system. By...
Failure detection and isolation in robotic manipulators using joint torque sensors
, Article Robotica ; Volume 28, Issue 4 , 2010 , Pages 549-561 ; 02635747 (ISSN) ; Aghili, F ; Sharif University of Technology
2010
Abstract
Reliability of any model-based failure detection and isolation (FDI) method depends on the amount of uncertainty in a system model. Recently, it has been shown that the use of joint torque sensing results in a simplified manipulator model that excludes hardly identifiable link dynamics and other nonlinearities such as friction, backlash, and flexibilities. In this paper, we show that the application of the simplified model in a fault detection algorithm increases reliability of fault monitoring system against modeling uncertainty. The proposed FDI filter is based on a smooth velocity observer of degree 2n where n stands for the number of manipulator joints. No velocity measurement and...
Clearing an orthogonal polygon to find the evaders
, Article Theoretical Computer Science ; Volume 847 , December , 2020 , Pages 175-184 ; Ghodsi, M ; Sharif University of Technology
Elsevier B. V
2020
Abstract
In a multi-robot system, a number of autonomous robots would sense, communicate, and decide to move within a given domain to achieve a common goal. In the pursuit-evasion problem, a polygonal region is given and a robot called a pursuer tries to find some mobile targets called evaders. The goal of this problem is to design a motion strategy for the pursuer such that it can detect all the evaders. In this paper, we consider a new variant of the pursuit-evasion problem in which the robots (pursuers) each moves back and forth along an orthogonal line segment inside a simple orthogonal polygon P. We assume that P includes unpredictable, moving evaders that have bounded speed. We propose the...
The wide-open three-legged parallel robot for long-bone fracture reduction
, Article Journal of Mechanisms and Robotics ; Volume 9, Issue 1 , 2017 ; 19424302 (ISSN) ; Farahmand, F ; Gallardo Alvarado, J ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2017
Abstract
Robotic reduction of long bones is associated with the need for considerable force and high precision. To balance the accuracy, payload, and workspace, we have designed a new six degrees-offreedom three-legged wide-open robotic system for long-bone fracture reduction. Thanks to the low number of legs and their nonsymmetrical configuration, the mechanism enjoys a unique architecture with a frontally open half-plane. This facilitates positioning the leg inside the mechanism and provides a large workspace for surgical maneuvers, as shown and compared to the well-known Gough-Stewart platform. The experimental tests on a phantom reveal that the mechanism is well capable of applying the desired...
Robust decentralized position/force control of cooperative robots without velocity measurement
, Article 2005 IEEE International Conference on Industrial Technology, ICIT 2005, Hong Kong, 14 December 2005 through 17 December 2005 ; Volume 2005 , 2005 , Pages 1403-1408 ; 0780394844 (ISBN); 9780780394841 (ISBN) ; Elhamifar, E ; Sharif University of Technology
2005
Abstract
A decentralized control scheme for multiple cooperative manipulators system is developed to achieve the desired performance in motion and force tracking in the presence of uncertainties in the dynamic equations of the robots. To reduce the effects of uncertainties in the closed-loop performance, a robust control algorithm using a robustifying term is proposed. Based on the Lyapunov stability method, it is proved that all the signals in the closed-loop, composed of a robot, an observer and a controller are uniformly ultimately bounded. Also to avoid the difficulties of using velocity sensors within the hand architecture an output feedback control scheme with a linear observer is used. © 2005...
Mechanical Systems Using Nonlinear State Feedback
, M.Sc. Thesis Sharif University of Technology ; Namvar, Mehrzad (Supervisor)
Abstract
Disturbance is one of the inseparable components of the mechanical systems which cannot be avoided. In these systems a number of inner and outer sources exist which are the cause of disturbance. Abrupt changes in torque, uncertainty in parameters, mechanical impulses and external forces on robot’s parts all can be mentioned as examples which introduce disturbance that affects the output of mechanical and robotic systems. Therefore, disturbance rejection is considered indispensable in robotic control systems. There are number of problems which are associated with disturbance rejection. In several methods, mostly optimization based methods, system fails to completely reject the disturbance and...
Design of a force-reflective master robot for haptic telesurgery applications: RoboMaster1
, Article Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS ; 2011 , Pages 7037-7040 ; 1557170X (ISSN) ; 9781424441211 (ISBN) ; Mirbagheri, A ; Salarieh, H ; Farahmand, F ; Sharif University of Technology
Abstract
With the increasing trend toward Minimally Invasive Surgery (MIS) procedures, the need to develop new robotic systems to facilitate such surgeries is more and more recognized. This paper describes the design and development of a 4 DOF force-reflective master robot (RoboMaster1) for haptic telesurgery applications. A two-double parallelogram robot is introduced including a novel mechanism at the base for producing and control of the end effector's linear motion. This eliminates the deficiencies caused due to suspending massive actuators at the end effector or cabling from the base. The kinematics and work space of the system were analyzed and a prototype was developed for primary practical...
Fast estimation of space-robots inertia parameters: A modular mathematical formulation
, Article Acta Astronautica ; Volume 127 , 2016 , Pages 283-295 ; 00945765 (ISSN) ; Malaek, S. M. B ; Sharif University of Technology
Elsevier Ltd
Abstract
This work aims to propose a new technique that considerably helps enhance time and precision needed to identify "Inertia Parameters (IPs)" of a typical Autonomous Space-Robot (ASR). Operations might include, capturing an unknown Target Space-Object (TSO), "active space-debris removal" or "automated in-orbit assemblies". In these operations generating precise successive commands are essential to the success of the mission. We show how a generalized, repeatable estimation-process could play an effective role to manage the operation. With the help of the well-known Force-Based approach, a new "modular formulation" has been developed to simultaneously identify IPs of an ASR while it captures a...
Morphological reconfiguration monitoring for homogeneous self-reconfigurable robots
, Article 2017 14th International Conference on Electrical Engineering, Computing Science and Automatic Control, CCE 2017, 20 September 2017 through 22 September 2017 ; 2017 ; 9781538634059 (ISBN) ; Tehrani, A. K. N ; Khodayar, M ; Sharif University of Technology
Abstract
Morphological computation (MC) has revolutionized robotic systems employing morphological properties (MP). Thus far, morphology has been mostly used to analyze morphological functionalities qualitatively after design phase of robotic systems. Furthermore, morphology has verified qualitative requirements, not modeled quantitative specifications. To fill this gap, we present a distributed algorithm to monitor module reconfiguration for homogeneous self-reconfigurable robots (HSRs) considering the size of modules. In this method, neighboring modules of a particular module occupy a spatial region called adjacency configuration (AC), whose size depends on the module size; then, we monitor...
A review on the features, performance and potential applications of hydrogel-based wearable strain/pressure sensors
, Article Advances in Colloid and Interface Science ; Volume 298 , 2021 ; 00018686 (ISSN) ; Shojaei, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Over the past few years, development of wearable devices has gained increasing momentum. Notably, the demand for stretchable strain sensors has significantly increased due to many potential and emerging applications such as human motion monitoring, prosthetics, robotic systems, and touch panels. Recently, hydrogels have been developed to overcome the drawbacks of the elastomer-based wearable strain sensors, caused by insufficient biocompatibility, brittle mechanical properties, complicated fabrication process, as the hydrogels can provide a combination of various exciting properties such as intrinsic electrical conductivity, suitable mechanical properties, and biocompatibility. There are...
A new approach for optimal control of multiple- Arm robotic systems
, Article IFAC Proceedings Volumes (IFAC-PapersOnline) ; Volume 16 , 2005 , Pages 313-318 ; 14746670 (ISSN); 008045108X (ISBN); 9780080451084 (ISBN) ; Babazadeh, A ; Sharif University of Technology
IFAC Secretariat
2005
Abstract
Optimal control frameworks are very important in optimization of multiple-arm robotic systems, although complexity, non-linearity and having large scales usually cause some computational problems in the capacity and time needed. in this paper, it is shown how by conducting the study of multiple-arm robotic systems, within a decomposition-coordination framework, the overall optimum can be achieved in only a few iterations. By using this methodology, the overall problem is considered as optimization of a two-level large-scale system. So with the aim of optimization, the problem is first decomposed into m sub-problems at the first level, where each sub-problem is solved using a typical gradient...
Optimization of kinematic redundancy and workspace analysis of a dual-arm cam-lock robot
, Article Robotica ; Volume 34, Issue 1 , 2016 , Pages 23-42 ; 02635747 (ISSN) ; Ghaemi Osgouie, K ; Meghdari, A ; Sharif University of Technology
Cambridge University Press
2016
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...
Two-Level Intelligent Control of Multiple Robotic Arms
, Ph.D. Dissertation Sharif University of Technology ; Sadati, Naser (Supervisor)
Abstract
This thesis presents a fuzzy-based interaction prediction approach (F-IPA) for two-level optimal control of large-scale systems. The design procedure uses a decomposition/coordination framework of hierarchical structures. At the first level, the system is decomposed into subsystems for which subproblems are formed. At the second level, a fuzzy coordinator is used to predict the coordination parameters needed to coordinate the solutions of the first level subproblems. The fuzzy coordinator uses a critic vector to evaluate its performance and learn its parameters by minimizing an energy function. The proposed control scheme is implemented on a two-degrees-of-freedom (2DOF) model of robot...
Optimal Multi-agent Formation Control of Quadcopters
, M.Sc. Thesis Sharif University of Technology ; Rezaeizadeh, Amin (Supervisor)
Abstract
In today's world, mobile robots have many applications in defense, transportation and industry. A robot may not be able to handle a mission alone or there may be different roles to perform a mission that a robot alone cannot perform, so the need to work with team robots is felt to the Necessary that by development Robot Technology and Advances in Communication, Microelectronics, Computing Technology, and Multi - Factor Expansion, robotic systems are widely used in theoretical research due to their flexibility, robustness, and scalability. In this research, robots are controlled in a coordinated manner as a team. In this research, algorithms were developed so that in a two and...
Design optimization of gimbal robotic joints based on task space manipulability
, Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010 ; Volume 3 , July , 2010 , Pages 567-572 ; 9780791849170 (ISBN) ; Hemmatian, I ; Ghaemi Osgouie, K ; Sharif University of Technology
2010
Abstract
Featuring a nonlinear novel design, Gimbal transmission, is a replacement for traditional robotic joints like gearboxes and revolute joints. This mechanism is one of the most recent types of nonlinear direct transmission (DT) methods in robots. As an alternative for traditional drive methodologies - herein called direct drive transmission (DD) methods, DT provides dynamic coupling and joint interaction attenuation while its capability to be adjusted for a desired task space point, smooth input-output characteristic, and varying reduction ratio lead to a desired force and motion behavior for the whole manipulator. In this paper, design optimization of a gimbal mechanism used as a replacement...
Deployment of multi-agent robotic systems in presence of obstacles
, Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010, Istanbul ; Volume 5 , 2010 , Pages 7-12 ; 9780791849194 (ISBN) ; Sayyaadi, H ; Sharif University of Technology
2010
Abstract
The deployment of multi-agent systems in presence of obstacle deals with autonomous motion of agents toward a specified target by sensing each other and boundaries of obstacles. In this paper, asynchronous, scalable, distributed algorithm is used to deploy agents. Boundaries of obstacles are modeled by virtual agents. Algorithm was implemented by solving continuous n-median problem called generalized Fermat-Weber problem. It is shown that deployment is performed when position of real agents are the geometric median of their Voronoi cells. Simulation results show the validity of the proposed algorithm very well