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teleoperation-systems
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Improvement of operator position prediction in teleoperation systems with time delay: Simulation and experimental studies on Phantom Omni devices
, Article Jordan Journal of Mechanical and Industrial Engineering ; Volume 13, Issue 3 , 2019 , Pages 197-205 ; 19956665 (ISSN) ; Nikpour, M ; Beigzadeh, B ; Meghdari, A ; Sharif University of Technology
Hashemite University
2019
Abstract
An online operator position prediction approach based on artificial neural network for teleoperation systems is proposed in this paper, which predicts future position of operator's hand based on current available data. The neural network gathers inputs for some time at the beginning of the operation, then is trained, and is finally exploited through the rest of the operation. Superiority of the proposed approach can be investigated from two aspects. Firstly, no limiting assumption is required in this approach in contrast with the proposed methods in the literature. Secondly, unknown operator intention can be dealt with in real time if it is not too sudden and unpredictable. Two different...
Adaptive online prediction of operator position in teleoperation with unknown time-varying delay: simulation and experiments
, Article Neural Computing and Applications ; 2020 ; Yazdankhoo, B ; Beigzadeh, B ; Meghdari, A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2020
Abstract
One of the most important problems in teleoperation systems is time delay and packet loss in the communication channel, which can affect transparency and stability. One way to overcome the time delay effects in a teleoperation system is to predict the master-side motion. In this way, when data is received in the slave side, it will be considered as the current position of the master robot and, thus, complete transparency could be achieved. The majority of the previous works regarding operator position prediction have considered known and constant time delay in the system; however, in the real applications, time delay is unknown and variable. In this paper, an adaptive online prediction...
Development of a Control Method for Realizing Flexible Motion in Medical Robots
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Gholamreza (Supervisor) ; Behzadipour, Saeed (Supervisor)
Abstract
The main purpose of this project is to propose a control method for medical robots (such as rehabilitation and surgical robots), such that they can be moved conveniently by the users’s hand while he senses a controllable resistance. For that purpose, a Model Reference Adaptive Impedance Control method is developed for controlling the robot end-effector impedance in Cartesian coordinates. The proposed nonlinear controller and the desired impedance model are presented in Cartesian coordinates of the robot end-effector which is sensible for the human user. The adaptation law is derived and a corresponding Lyapunov stability is provided to prove the asymptotic tracking of the impedance model. By...
Nonlinear bilateral adaptive impedance control with applications in telesurgery and telerehabilitation
, Article Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME ; Volume 138, Issue 11 , 2016 ; 00220434 (ISSN) ; Behzadipour, S ; Salarieh, H ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
Abstract
A bilateral nonlinear adaptive impedance controller is proposed for the control of multi-degrees-of-freedom (DOF) teleoperation systems. In this controller, instead of conventional position and/or force tracking, the impedance of the nonlinear teleoperation system is controlled. The controller provides asymptotic tracking of two impedance models in Cartesian coordinates for the master and slave robots. The proposed bilateral controller can be used in different medical applications, such as telesurgery and telerehabilitation, where the impedance of the robot in interaction with human subject is of great importance. The parameters of the two impedance models can be adjusted according to the...
Patient-Robot-therapist collaboration using resistive impedance controlled tele-robotic systems subjected to time delays
, Article Journal of Mechanisms and Robotics ; Volume 10, Issue 6 , 2018 ; 19424302 (ISSN) ; Salarieh, H ; Behzadipour, S ; Tavakoli, M ; Sharif University of Technology
Abstract
In this paper, an approach to physical collaboration between a patient and a therapist is proposed using a bilateral impedance control strategy developed for delayed tele-robotic systems. The patient performs a tele-rehabilitation task in a resistive virtual environment with the help of online assistive forces from the therapist being provided through teleoperation. Using this strategy, the patient's involuntary hand tremors can be filtered out and the effort of severely impaired patients can be amplified in order to facilitate their early engagement in physical tasks. The response of the first desired impedance model is tracked by the master robot (interacting with the patient), and the...
Adaptive online prediction of operator position in teleoperation with unknown time-varying delay: simulation and experiments
, Article Neural Computing and Applications ; Volume 33, Issue 13 , 2021 , Pages 7575-7592 ; 09410643 (ISSN) ; Yazdankhoo, B ; Beigzadeh, B ; Meghdari, A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
One of the most important problems in teleoperation systems is time delay and packet loss in the communication channel, which can affect transparency and stability. One way to overcome the time delay effects in a teleoperation system is to predict the master-side motion. In this way, when data is received in the slave side, it will be considered as the current position of the master robot and, thus, complete transparency could be achieved. The majority of the previous works regarding operator position prediction have considered known and constant time delay in the system; however, in the real applications, time delay is unknown and variable. In this paper, an adaptive online prediction...
Nonlinear Bilateral Adaptive Impedance Control with Applications in Medical Robotics
, Ph.D. Dissertation Sharif University of Technology ; Salarieh, Hassan (Supervisor) ; Behzadipour, Saeed (Supervisor) ; Tavakoli, Mahdi (Co-Advisor)
Abstract
In recent years, teleoperation systems have been widely used in bio-medical applications such as minimally invasive telesurgery, telerehabilitation and telesonography, and also for outer space exploration and radioactive material management. In bilateral teleoperation systems, the human operator applies force on the master robot to control the position of the slave robot in order to perform a task in a remote environment. A nonlinear robust adaptive bilateral impedance control strategy is proposed in this research to provide the absolute stability of multi-DOF teleoperation systems with communication delays. Using this controller, instead of conventional position tracking (synchronization)...
Control design and passivity analysis for scaled one-dimensional bilateral teleoperated nanomanipulation
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings, 13 November 2009 through 19 November 2009 ; Volume 10, Issue PART A , 2010 , Pages 279-285 ; 9780791843833 (ISBN) ; Vossoughi, G. R ; Ahmadian, M. T ; Tajaddodianfar, F ; Sharif University of Technology
Abstract
In this paper, a novel control approach for onedimensional bilateral teleoperated nanomanipulation system is proposed. While manipulating objects with a nanomanipulator, real time visual feedback is not available. So, force feedback is used to compensate for the lack of visual information. Since nanometer scale forces are dominated by surface forces instead of inertial forces as in macro world, scaling of nanoforces is one of the major issues of teleoperation system. The Hertz elastic contact model is used to model the interactions between the slave robot and the environment. The proposed approach uses the simple proportional derivative control, i.e., the master and slave robots are...
Stable nonlinear trilateral impedance control for dual-user haptic teleoperation systems with communication delays
, Article Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME ; Volume 139, Issue 12 , 2017 ; 00220434 (ISSN) ; Salarieh, H ; Behzadipour, S ; Tavakoli, M ; Sharif University of Technology
Abstract
A new nonlinear adaptive impedance-based trilateral controller is proposed to ensure the absolute stability of multi-degrees-of-freedom (DOFs) dual-user haptic teleoperation systems subjected to communication delays. Using this strategy, reference impedance models are realized for the trilateral teleoperation system represented by a three-port network to facilitate cooperation of two human operators in order to perform a remote physical task. For this purpose, an impedance model defines the desired haptic interaction between the two human operators, while another impedance model specifies the desired behavior of the slave robot in terms of tracking the mater robots' trajectories during...
Tele-echography of moving organs using an Impedance-controlled telerobotic system
, Article Mechatronics ; Volume 45 , 2017 , Pages 1339-1351 ; 09574158 (ISSN) ; Salarieh, H ; Behzadipour, S ; Tavakoli, M ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
A novel impedance-controlled teleoperation system is developed for robot-assisted tele-echography of moving organs such as heart, chest and breast during their natural motions (beating and/or breathing). The procedure of devising the two impedance models for the master and slave robots is developed such that (a) the slave robot holding the ultrasound (US) probe follows the master trajectory but complies with the oscillatory interaction force of the moving organ, and (b) the sonographer receives feedback from the non-oscillatory portion of the slave-organ interaction force via the master robot similar to the haptic feedback received in echography of a stationary organ. These goals are...
Robust adaptive bilateral control of teleoperation systems with uncertain parameters and unmodeled dynamics
, Article 5th RSI International Conference on Robotics and Mechatronics, IcRoM 2017, 25 October 2017 through 27 October 2017 ; 2018 , Pages 95-100 ; 9781538657034 (ISBN) ; Nazari, K ; Farahmand, F ; Sharif University of Technology
Abstract
Kinematic and dynamic parameters of robot manipulators are difficult to measure exactly. Also, time varying unknown dynamical parameters of human arm, during interaction with the master robot and unknown parameters of environment during interaction with the slave robot, in teleoperation systems, insert further uncertainties. Furthermore, unknown parameters, unmodeled dynamics of master/slave robots, human arm model and environment introduce more uncertainties. In this paper, a robust adaptive master-slave teleoperation control strategy is introduced which require neither the exact knowledge about the parameters of the master/slave robots, human arm and environment, because of the...
Impedance control of non-linear multi-DOF teleoperation systems with time delay: absolute stability
, Article IET Control Theory and Applications ; Volume 12, Issue 12 , 2018 , Pages 1722-1729 ; 17518644 (ISSN) ; Salarieh, H ; Behzadipour, S ; Tavakoli, M ; Sharif University of Technology
Abstract
A non-linear robust adaptive bilateral impedance controller is proposed to provide the absolute stability of multi-DOF teleoperation systems with communication delays, in addition to the force and position tracking performance. The proposed controller realises two desired (or reference) impedance models for the master and slave robots using a new non-linear robust version of the model reference adaptive control scheme. Using the absolute stability criterion, the robustness condition of the teleoperation system against communication delays is obtained, resulting in suitable adjustments of parameter values in the desired impedance models. In addition, using the Lyapunov stability theorem, the...
Assist-as-needed policy for movement therapy using telerobotics-mediated therapist supervision
, Article Control Engineering Practice ; Volume 101 , 2020 ; Behzadipour, S ; Salarieh, H ; Tavakoli, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this paper, a new impedance-based teleoperation strategy is proposed for assist-as-needed tele-rehabilitation via a multi-DOF telerobotic system having patient–master and therapist–slave interactions. Unlike a regular teleoperation system and as the main contribution of this work to minimize the therapist's movements, the therapist's hand only follows the patient's deviation from the target trajectory. Also it provides a better perception of the patient's problems in motor control to the therapist The admissible deviation of the patient's limb from a reference target trajectory is governed by an impedance model responding to both patient's and therapist's interaction forces. As the other...
Adaptive sliding mode control of a piezo-actuated bilateral teleoperated micromanipulation system
, Article Precision Engineering ; Volume 35, Issue 2 , 2011 , Pages 309-317 ; 01416359 (ISSN) ; Ahmadian, M. T ; Vossoughi, G ; Rezaei, S. M ; Zareinejad, M ; Sharif University of Technology
Abstract
Piezoelectric actuators are widely used in micro manipulation applications. However, hysteresis nonlinearity limits the accuracy of these actuators. This paper presents a novel approach for utilizing a piezoelectric nano-stage as the slave manipulator of a teleoperation system based on a sliding mode controller. The Prandtl-Ishlinskii (PI) model is used to model actuator hysteresis in feedforward scheme to cancel out this nonlinearity. The presented approach requires full state and force measurements at both the master and slave sides. Such a system is costly and also difficult to implement. Therefore, sliding mode unknown input observer (UIO) is proposed for full state and force...
Beating-heart robotic surgery using bilateral impedance control: Theory and experiments
, Article Biomedical Signal Processing and Control ; Volume 45 , 2018 , Pages 256-266 ; 17468094 (ISSN) ; Salarieh, H ; Behzadipour, S ; Tavakoli, M ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
A bilateral impedance controller is presented to enable robot-assisted surgery of a beating heart. For this purpose, two desired impedance models are designed and realized for the master and slave robots interacting with the operator (surgeon) and the environment (heart tissue), respectively. The impedance models are designed such that (a) the slave robot complies with the oscillatory motion of the beating heart and (b) the surgeon perceives the non-oscillatory portion of the slave/heart contact force at the master robot implying arrested-heart surgery. These performance goals are achieved via appropriate adjustment of the impedance model parameters without any measurement or estimation of...