Adaptive Fuzzy Computed-Torque Control for Robot Manipulator with Uncertain Dynamics

This paper proposes two types of adaptive control schemes combined by the conventional computed-torque control and different fuzzy compensators for the robust tracking control of robotic manipulators with structured and unstructured uncertainties. Fuzzy compensators based on feed-forward and feed-back are developed to compensate these modeling uncertainties. The validity of the two types of adaptive control schemes is shown by numerical simulations of a three link rotary robot manipulator.

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Comparative performance analysis of PD/PID computed torque control, filtered error approximation based control and NN control for a robot manipulator

2015 IEEE UP Section Conference on Electrical Computer and Electronics (UPCON) ◽

10.1109/upcon.2015.7456706 ◽

2015 ◽

Cited By ~ 5

Author(s):

Eshita Rastogi ◽

Lal Bahadur Prasad

Keyword(s):

Performance Analysis ◽

Robot Manipulator ◽

Torque Control ◽

Comparative Performance ◽

Computed Torque Control ◽

Filtered Error ◽

Computed Torque

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COMPUTED TORQUE CONTROL FOR A SPATIAL DISORIENTATION TRAINER

Facta Universitatis Series Mechanical Engineering ◽

10.22190/fume190919003v ◽

2020 ◽

Vol 18 (2) ◽

pp. 269

Author(s):

Jelena Vidaković ◽

Vladimir Kvrgić ◽

Mihailo Lazarević ◽

Pavle Stepanić

Keyword(s):

Control System ◽

Robot Control ◽

Inverse Dynamics ◽

Control Method ◽

Robot Manipulator ◽

Training System ◽

Torque Control ◽

Spatial Disorientation ◽

Computed Torque Control ◽

Computed Torque

A development of a robot control system is a highly complex task due to nonlinear dynamic coupling between the robot links. Advanced robot control strategies often entail difficulties in implementation, and prospective benefits of their application need to be analyzed using simulation techniques. Computed torque control (CTC) is a feedforward control method used for tracking of robot’s time-varying trajectories in the presence of varying loads. For the implementation of CTC, the inverse dynamics model of the robot manipulator has to be developed. In this paper, the addition of CTC compensator to the feedback controller is considered for a Spatial disorientation trainer (SDT). This pilot training system is modeled as a 4DoF robot manipulator with revolute joints. For the designed mechanical structure, chosen actuators and considered motion of the SDT, CTC-based control system performance is compared with the traditional speed PI controller using the realistic simulation model. The simulation results, which showed significant improvement in the trajectory tracking for the designed SDT, can be used for the control system design purpose as well as within mechanical design verification.

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Model-assisted extended state observer-based computed torque control for trajectory tracking of uncertain robotic manipulator systems

International Journal of Advanced Robotic Systems ◽

10.1177/1729881418801738 ◽

2018 ◽

Vol 15 (5) ◽

pp. 172988141880173 ◽

Cited By ~ 4

Author(s):

Chao Chen ◽

Chengrui Zhang ◽

Tianliang Hu ◽

Hepeng Ni ◽

WeiChao Luo

Keyword(s):

Trajectory Tracking ◽

Robotic Manipulators ◽

State Observer ◽

Torque Control ◽

Extended State Observer ◽

Effective Control ◽

Extended State ◽

Uncertain Dynamics ◽

Computed Torque Control ◽

Computed Torque

Computed torque control is an effective control scheme for trajectory tracking of robotic manipulators. However, computed torque control requires precise dynamic models of robotic manipulators and is severely affected by uncertain dynamics. Thus, a new scheme that combines a computed torque control and a novel model-assisted extended state observer is developed for the robust tracking control of robotic manipulators subject to structured and unstructured uncertainties to overcome the disadvantages of computed torque control and exploit its merits. The model-assisted extended state observer is designed to estimate and compensate these uncertain dynamics as a lumped disturbance online, which further improves the disturbance rejection property of a robotic system. Global uniform ultimate boundedness stability with an exponential convergence of a closed-loop system is verified through Lyapunov method. Simulations are performed on a two degree-of-freedom manipulator to verify the effectiveness and superiority of the proposed controller.

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A Comparison of Computed Torque Control and Sliding Mode Control for a Three Link Robot Manipulator

2018 International Conference on Computing, Power and Communication Technologies (GUCON) ◽

10.1109/gucon.2018.8675048 ◽

2018 ◽

Cited By ~ 1

Author(s):

Nirbhay Kumar Chaturvedi ◽

L. B. Prasad

Keyword(s):

Sliding Mode Control ◽

Sliding Mode ◽

Robot Manipulator ◽

Torque Control ◽

Mode Control ◽

Computed Torque Control ◽

Computed Torque

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Optimal adaptive computed torque control for haptic-teleoperation system with uncertain dynamics

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/09596518211048035 ◽

2021 ◽

pp. 095965182110480

Author(s):

Tayfun Abut ◽

Servet Soyguder

Keyword(s):

Real Time ◽

Optimization Algorithm ◽

Control Method ◽

Torque Control ◽

Gray Wolf ◽

Uncertain Dynamics ◽

Computed Torque Control ◽

Dynamic Uncertainty ◽

Control Coefficients ◽

Computed Torque

This study aimed to eliminate dynamic uncertainty, one of the main problems of haptic teleoperation robotic systems. The optimal adaptive computed torque control method was used to overcome this problem. As is known, excellent stability and transparency are required in teleoperation systems. However, dynamic uncertainty that causes stability problems in the control of these systems also causes poor performance. In conventional adaptive computed torque control methods, updating the parameters of the system is generally discussed, but updating the control coefficients of vital importance in the control of the system is not considered. In the proposed method, an adaptation rule has been created to update uncertain parameters. In addition, the gray wolf optimization algorithm, one of the current optimization algorithms, has been proposed and applied to obtain the control coefficients of the system. The position tracking stability of the system was examined by using Lyapunov stability analysis method. As a result, both simulation and real-time optimal adaptive computational torque control method were used and bilateral position and force control was performed and the performance results of the system are obtained graphically and examined. Optimal adaptive computed torque control method obtained using the gray wolf optimization algorithm was used first in the literature search and success results have been obtained. In this regard, the authors have the idea that this work is an innovative aspect of both simulation and real time with the optimal adaptive computed torque control method.

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