The Experts below are selected from a list of 27669 Experts worldwide ranked by ideXlab platform

Santhakumar Mohan - One of the best experts on this subject based on the ideXlab platform.

  • coordinated motion control in task space of an autonomous underwater vehicle Manipulator System
    Ocean Engineering, 2015
    Co-Authors: Santhakumar Mohan, Jinwhan Kim
    Abstract:

    This paper presents a coordinated motion control scheme using a disturbance observer in task space for an autonomous underwater vehicle–Manipulator System (UVMS). Since, the UVMS is kinematically redundant in nature, the proposed controller permits self-motion which can be utilized to perform power efficient trajectory tracking and at the same time it also assures that the System is able to track the given desired spatial trajectory with minimal errors (despite the presence of external disturbances, System uncertainties and internal noises). The performance of the proposed coordinated motion control of the UVMS is demonstrated numerically by simulating a few underwater tasks such as payload conveyance. The System’s disturbance compensation capabilities are shown and the effects of external disturbances and parameter uncertainties on the station keeping performance are also analyzed. A comparative analysis on power consumption is presented to prove the effectiveness of the proposed scheme.

  • a robust task space position tracking control of an underwater vehicle Manipulator System
    Artificial Intelligence Review, 2015
    Co-Authors: Santhakumar Mohan, Jinwhan Kim, Yogesh Singh
    Abstract:

    This paper addresses a robust tracking control of an autonomous underwater vehicle-Manipulator System (UVMS) based on terminal sling mode control in task space along with a disturbance observer. The effectiveness of the proposed scheme is demonstrated using numerical simulations having a serial planar Manipulator (two rotary joints) on an underwater vehicle in a horizontal plane. An inverse dynamic solution for the System is obtained using the Newton-Euler method incorporating hydrodynamic and dynamic coupling effects. Performance of the proposed scheme is compared under various control schemes and demonstrated numerically for a predefined trajectory of the end effector (in task space).

  • indirect adaptive control of an autonomous underwater vehicle Manipulator System for underwater manipulation tasks
    Ocean Engineering, 2012
    Co-Authors: Santhakumar Mohan
    Abstract:

    Abstract This paper presents an indirect adaptive control method for an autonomous underwater vehicle-Manipulator System (UVMS) based on an extended Kalman filter (EKF). This method overcomes the disadvantages of existing disturbance observers and direct adaptive control schemes, which are based on linear System techniques and regressor-based techniques. The proposed control scheme can be applied to UVMSs for various purposes such as payload compensation, interaction effects compensation, underwater current or external disturbance compensation, reaction compensation, and independent System control. The performance of the proposed controller was demonstrated numerically by payload compensation, where it compensated for the reaction effects experienced during a manipulation task, and disturbance (underwater current) compensation in a UVMS with a six degrees of freedom (DOF) underwater vehicle and a 3-DOF underwater Manipulator.

Rui Wang - One of the best experts on this subject based on the ideXlab platform.

  • grasping marine products with hybrid driven underwater vehicle Manipulator System
    IEEE Transactions on Automation Science and Engineering, 2020
    Co-Authors: Mingxue Cai, Yu Wang, Shuo Wang, Rui Wang, Yong Ren, Min Tan
    Abstract:

    This article presents the comprehensive framework for a hybrid-driven underwater vehicle-Manipulator System (HD-UVMS) to grasp marine products on the seabed. The purpose of the proposed hybrid-driven propulsion System is to improve the swimming ability of the HD-UVMS by using thrusters and enhance the stability of its pose adjustment mechanism via two unique long fin propulsors. The control mode for the thrusters and long fin propulsors is based on a fuzzy logic control method. Subsequently, a lightweight Manipulator is developed to grasp marine products. The open–closed angle and current controls for the gripper help to avoid damaging marine products. A vision System is installed to enable the HD-UVMS to gradually approach marine products with the aid of monocular vision and grasp them with the aid of binocular vision. A detailed method for monocular passive ranging and stereo matching, in accordance with real-time metrics, is elaborated. Finally, relevant experiments are conducted in an indoor pool and under real sea condition to assess the effectiveness of the proposed framework. Note to Practitioners —The motivation behind this article is the design of an underwater vehicle-Manipulator System that can grasp marine products on the real seabed and perform other underwater intervention tasks. Currently, the predominant method of fishing for marine products relies on human divers, which has disadvantages for human divers’ health due to the long periods of time spent working underwater. In order to further study the problem, this article develops a hybrid-driven underwater vehicle-Manipulator System (HD-UVMS) to work in a real seabed environment. A hybrid-driven motion control framework is presented using the thrusters to achieve effective cruising and searching for marine products and long fin propulsors for the fine pose adjustment required to grasp marine products. The proposed lightweight underwater Manipulator can grasp marine products on the seabed with the aid of a vision System. A series of experiments suggests that the HD-UVMS is practical and valid.

  • Floating Autonomous Manipulation of the Underwater Biomimetic Vehicle-Manipulator System: Methodology and Verification
    IEEE Transactions on Industrial Electronics, 2018
    Co-Authors: Chong Tang, Yu Wang, Shuo Wang, Rui Wang
    Abstract:

    This paper addresses the achievement of floating autonomous manipulation of the underwater biomimetic vehicle-Manipulator System (UBVMS). A practical vehicle-Manipulator coordinated plan and control methodology of the UBVMS for autonomous interventions are designed. First, the System configuration is introduced, and the optimal work space is confirmed. Then, the control framework of the UBVMS mainly consisting of online motion planning, multitask kinematic control, dynamic feedforward compensation, and adaptive parameter undulatory control for autonomous manipulation is presented. The online motion planning method with resort to tracking differentiator is developed to produce desired task trajectory and reference rate. The singularity-robust multitask kinematic control algorithm with state observers is designed to obtain System reference velocity. The couple influence on the vehicle induced by the presence of the Manipulator is described as the dynamic feedforward compensation signal to reduce undesired waggle of the UBVMS. Adaptive parameter modifier of the biomimetic propulsor is designed to satisfy multifarious performance requirements in different motion phases. Finally, pool experiments in multiple scenarios for autonomous grasping manipulation are conducted to verify the effectiveness and adaptability of the developed coordinated plan and control strategy.

G Casalino - One of the best experts on this subject based on the ideXlab platform.

  • whole body control of a dual arm underwater vehicle Manipulator System
    Annual Reviews in Control, 2015
    Co-Authors: Enrico Simetti, G Casalino
    Abstract:

    Abstract This paper presents a whole body control framework for the control of a dual arm underwater vehicle Manipulator System developed in the context of the MARIS Italian research project, which deals with the control and coordination of underwater vehicles for manipulation and transportation problems. The proposed framework is the extension of the one used in the successful TRIDENT FP7 project that has been improved to be able to deal with multidimensional inequality control objectives. After the presentation of the mathematical background, the paper presents some simulation results showing the good performances of the proposed algorithm.

Yogesh Singh - One of the best experts on this subject based on the ideXlab platform.

  • a robust task space position tracking control of an underwater vehicle Manipulator System
    Artificial Intelligence Review, 2015
    Co-Authors: Santhakumar Mohan, Jinwhan Kim, Yogesh Singh
    Abstract:

    This paper addresses a robust tracking control of an autonomous underwater vehicle-Manipulator System (UVMS) based on terminal sling mode control in task space along with a disturbance observer. The effectiveness of the proposed scheme is demonstrated using numerical simulations having a serial planar Manipulator (two rotary joints) on an underwater vehicle in a horizontal plane. An inverse dynamic solution for the System is obtained using the Newton-Euler method incorporating hydrodynamic and dynamic coupling effects. Performance of the proposed scheme is compared under various control schemes and demonstrated numerically for a predefined trajectory of the end effector (in task space).

M. O. Tokhi - One of the best experts on this subject based on the ideXlab platform.

  • vibration control of a very flexible Manipulator System
    Control Engineering Practice, 2005
    Co-Authors: Zahar Mohamed, M. O. Tokhi, Jorge Martins, J Sa M G Da Costa, Miguel Ayala Botto
    Abstract:

    This paper presents experimental investigations into the development of feedforward and feedback control schemes for vibration control of a very flexible and high-friction Manipulator System. A feedforward control scheme based on input shaping and low-pass filtering techniques and a strain feedback control scheme are examined. To study the effectiveness of the controllers, initially a collocated PD control is developed for control of rigid body motion. The performances of the controllers are assessed in terms of the input tracking capability and vibration reduction as compared to the response with PD control. Moreover, the robustness of the feedforward control schemes is discussed. Finally, a comparative assessment of the control strategies is presented.

  • Dynamic characterisation of a flexible Manipulator System
    Robotica, 2001
    Co-Authors: M. O. Tokhi, Zaharuddin Mohamed, Mohammad Hasan Shaheed
    Abstract:

    This paper presents theoretical and experimental investigations into the dynamic modelling and characterisation of a flexible Manipulator System. A constrained planar single-link flexible Manipulator is considered. A dynamic model of the System is developed based on finite element methods. The flexural and rigid dynamics of the System as well as inertia effects and structural damping are accounted in the model. Performance of the algorithm in describing the dynamic behaviour of the System is assessed in comparison to an experimental test-rig. Experimental results are presented for validation of the developed finite element model in the time and frequency domains.

  • dynamic modelling of a flexible Manipulator System incorporating payload theory and experiments
    Journal of Low Frequency Noise Vibration and Active Control, 2000
    Co-Authors: M. O. Tokhi, Zaharuddin Mohamed, Mohammad Hasan Shaheed
    Abstract:

    This paper presents theoretical and experimental investigations into the dynamic characterisation of a flexible Manipulator System. A constrained planar single-link flexible Manipulator is considered. A dynamic model of the System, incorporating structural damping, hub inertia and payload, is developed using finite element methods. Effects of damping and payload on the response of the flexible Manipulator are discussed. Performance of the algorithm in describing the dynamic behaviour of the System is assessed in comparison to an experimental test-rig. Experimental results are presented for validation of the developed finite element model in the time and frequency domains.

  • dynamic characterisation of a flexible Manipulator System theory and experiments
    IEEE Region 10 Conference, 2000
    Co-Authors: M. O. Tokhi, Zaharuddin Mohamed, S H M Amin, Rosbi Mamat
    Abstract:

    Presents theoretical and experimental investigations into the dynamic modelling and characterisation of a flexible Manipulator System. A constrained planar single-link flexible Manipulator is considered. A dynamic model of the System is developed based on finite element methods incorporating structural damping. Performance of the algorithm in describing the dynamic behaviour of the System is assessed in comparison to an experimental test-rig in the time and frequency domains.

  • Sequential and parallel real-time simulation of a flexible Manipulator System
    Robotica, 1998
    Co-Authors: M. O. Tokhi, Mohammed Alamgir Hossain, A. K. M. Azad
    Abstract:

    This paper presents an investigation into the utilisation of sequential and parallel processing techniques for the real-time simulation of a flexible Manipulator System. A finite dimensional simulation of the System is developed using a finite difference approximation to the governing dynamic equation of the Manipulator. The developed algorithm is implemented on a number of uni-processor and multi-processor, homogeneous and heterogeneous, parallel architectures. A comparison of the results of these implementations is made and discussed, on the basis of real-time processing requirements in the simulation and control of flexible Manipulator Systems.