Robust hybrid impedance control of robot manipulators via a tracking control method

2002 ◽  
Author(s):  
Guangjun Liu ◽  
A.A. Goldenberg
Keyword(s):  
Tracking Control ◽  
Control Method ◽  
Impedance Control ◽  
Robot Manipulators

scholarly journals A model reference adaptive variable impedance control method for robot

2021 ◽  
Vol 336 ◽  
pp. 03005
Author(s):  
Xinchao Sun ◽  
Lianyu Zhao ◽  
Zhenzhong Liu
Keyword(s):  
Real Time ◽  
Tracking Control ◽  
Control Method ◽  
Impedance Control ◽  
Tracking Error ◽  
Reference Trajectory ◽  
Control Parameters ◽  
Model Reference ◽  
Force Tracking ◽  
Model Reference Adaptive

As a simple and effective force tracking control method, impedance control is widely used in robot contact operations. The internal control parameters of traditional impedance control are constant and cannot be corrected in real time, which will lead to instability of control system or large force tracking error. Therefore, it is difficult to be applied to the occasions requiring higher force accuracy, such as robotic medical surgery, robotic space operation and so on. To solve this problem, this paper proposes a model reference adaptive variable impedance control method, which can realize force tracking control by adjusting internal impedance control parameters in real time and generating a reference trajectory at the same time. The simulation experiment proves that compared with the traditional impedance control method, this method has faster force tracking speed and smaller force tracking error. It is a better force tracking control method.

scholarly journals A Novel Fast Terminal Sliding Mode Tracking Control Methodology for Robot Manipulators

2020 ◽  
Vol 10 (9) ◽  
pp. 3010 ◽  
Author(s):  
Quang Vinh Doan ◽  
Anh Tuan Vo ◽  
Tien Dung Le ◽  
Hee-Jun Kang ◽  
Ngoc Hoai An Nguyen
Keyword(s):  
Tracking Control ◽  
High Performance ◽  
Control Method ◽  
Sliding Mode ◽  
Robot Manipulators ◽  
Convergence Time ◽  
Trajectory Tracking Control ◽  
Terminal Sliding Mode ◽  
Uncertain Dynamics ◽  
Fast Terminal Sliding Mode

This paper comes up with a novel Fast Terminal Sliding Mode Control (FTSMC) for robot manipulators. First, to enhance the response, fast convergence time, against uncertainties, and accuracy of the tracking position, the novel Fast Terminal Sliding Mode Manifold (FTSMM) is developed. Then, a Supper-Twisting Control Law (STCL) is applied to combat the unknown nonlinear functions in the control system. By using this technique, the exterior disturbances and uncertain dynamics are compensated more rapidly and more correctly with the smooth control torque. Finally, the proposed controller is launched from the proposed sliding mode manifold and the STCL to provide the desired performance. Consequently, the stabilization and robustness criteria are guaranteed in the designed system with high-performance and limited chattering. The proposed controller runs without a precise dynamic model, even in the presence of uncertain components. The numerical examples are simulated to evaluate the effectiveness of the proposed control method for trajectory tracking control of a 3-Degrees of Freedom (DOF) robotic manipulator.

scholarly journals Adaptive Fast Nonsingular Fixed-Time Tracking Control for Robot Manipulators

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Huihui Pan ◽  
Guangming Zhang
Keyword(s):  
Trajectory Tracking ◽  
Tracking Control ◽  
Control Method ◽  
Sliding Mode ◽  
Robot Manipulators ◽  
Fixed Time ◽  
Convergence Time ◽  
Trajectory Tracking Control ◽  
Uncertain Dynamics ◽  
Adaptive Technique

This paper studies the fixed-time trajectory tracking control problem of robot manipulators in the presence of uncertain dynamics and external disturbances. First, a novel nonsingular fixed-time sliding mode surface is presented, which can ensure that the convergence time of the suggested surface is bounded regardless of the initial states. Subsequently, a novel fast nonsingular fixed-time sliding mode control (NFNFSMC) is developed so that the closed-loop system is fixed-time convergent to the equilibrium. By applying the proposed NFNFSMC method and the adaptive technique, a novel adaptive nonsingular fixed-time control scheme is proposed, which can guarantee fast fixed-time convergence of the tracking errors to small regions around the origin. With the proposed control method, the lumped disturbance is compensated by the adaptive technique, whose prior information about the upper bound is not needed. The fixed-time stability of the trajectory tracking control under the proposed controller is proved by the Lyapunov stability theory. Finally, corresponding simulations are given to illustrate the validity and superiority of the proposed control approach.

scholarly journals Trajectory Tracking Control of Robot Manipulators Based on U-Model

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Xianghua Ma ◽  
Yang Zhao ◽  
Yiqun Di
Keyword(s):  
Trajectory Tracking ◽  
Tracking Control ◽  
Control Algorithm ◽  
Control Method ◽  
Robot Manipulators ◽  
Computation Time ◽  
Initial State ◽  
Trajectory Tracking Control ◽  
Model Method ◽  
Trajectory Tracking Controller

A new trajectory tracking control method based on the U-model is proposed to improve the trajectory tacking speed of robot manipulators. The U-model method is introduced to relieve the requirement of the dynamic mathematical model and make the design of trajectory tracking controller of robot manipulators simpler. To further improve the trajectory tacking speed, an improved iterative learning control algorithm is used to suppress the influence of the initial state error with less computation time. Experimental results show that the proposed control method is effective and practical for the trajectory tracking control of robot manipulators, especially with a high real-time requirement.

scholarly journals Disturbance Observer-Based Robot End Constant Contact Force-Tracking Control

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-20 ◽  
Author(s):  
Tie Zhang ◽  
Xiaohong Liang
Keyword(s):  
Contact Force ◽  
Tracking Control ◽  
Disturbance Observer ◽  
Control Method ◽  
Sliding Mode ◽  
Impedance Control ◽  
Joint Torque ◽  
Estimation Accuracy ◽  
Force Tracking ◽  
High Control

A disturbance observer-based hybrid sliding mode impedance control method is proposed in this paper, which is able to achieve robot end constant contact force-tracking control without force/torque sensors. The method requires only the values of joint torque, joint angle, and joint angular velocity, which are converted by robot servo motor signals, to implement the control. The control scheme consists of two parts: one is a disturbance observer and the other is a hybrid sliding mode impedance controller. The disturbance observer, which takes robot internal signals mentioned above as the inputs to estimate the robot end contact force, is designed based on generalized momentum, thus improving the estimation accuracy. The hybrid sliding mode impedance controller, which uses the values estimated by the disturbance observer and the robot internal signals as the inputs to calculate the corresponding position adjustment, integrates both the impedance control and sliding mode control, thus improving the force-tracking performance and robustness. Experimental results show that the proposed disturbance observer-based hybrid sliding mode impedance control method possesses high control precision.

scholarly journals Compensator-critic structure-based event-triggered decentralized tracking control of modular robot manipulators: theory and experimental verification

2021 ◽  
Author(s):  
Bing Ma ◽  
Yuanchun Li
Keyword(s):  
Tracking Control ◽  
Control Method ◽  
Robot Manipulators ◽  
Tracking Error ◽  
Adaptive Dynamic Programming ◽  
Joint Torque ◽  
Local Dynamic ◽  
Modular Robot ◽  
Hamilton Jacobi Bellman ◽  
Event Triggered

AbstractThis paper presents a novel compensator-critic structure-based event-triggered decentralized tracking control of modular robot manipulators (MRMs). On the basis of subsystem dynamics under joint torque feedback (JTF) technique, the proposed tracking error fusion function, which includes position error and velocity error, is utilized to construct performance index function. By analyzing the dynamic uncertainties, a local dynamic information-based robust controller is designed to engage the model uncertainty compensation. Based on adaptive dynamic programming (ADP) algorithm and the event-triggered mechanism, the decentralized tracking control is obtained by solving the event-triggered Hamilton–Jacobi–Bellman equation (HJBE) with the critic neural network (NN). The tracking error of the closed-loop manipulators system is proved to be ultimately uniformly bounded (UUB) using the Lyapunov stability theorem. Finally, experimental results illustrate the effectiveness of the developed control method.

scholarly journals A Novel Decentralized Fixed-Time Tracking Control for Modular Robot Manipulators: Theoretical and Experimental Verification

2021 ◽  
Author(s):  
Zengpeng Lu ◽  
Yuanchun Li ◽  
Yan Li
Keyword(s):  
Tracking Control ◽  
Control Method ◽  
Robot Manipulators ◽  
Fixed Time ◽  
Convergence Time ◽  
Modular Robot ◽  
Total Uncertainty ◽  
Control Approach ◽  
Time Control ◽  
Tracking Ability

Abstract This paper presents a novel decentralized fixed-time tracking control approach, which realizes the advantages of modular robot manipulators (MRMs) with fixed-time convergence, strong robustness, and high tracking performance. First, to estimate the total uncertainty of MRMs, the fixed-time observer based on the extended state is developed. Then, combined with the disturbance observer, a novel decentralized control method based on a fixed-time control strategy was devised to accomplish global fixed-time convergence of MRMs. And, stability analysis based on Lyapunov is utilized to obtain the fixed-time stability as well as convergence time of MRMs. Finally, numerical analysis and experiment respectively verify the excellent tracking ability of the presented decentralized fixed-time tracking control.

Development of an Active Worktable and Its Application to Force Control of Robot Manipulators

2000 ◽  
Vol 12 (3) ◽  
pp. 249-253
Author(s):  
Shin-ichi Nakajima ◽  
Keyword(s):  
Force Control ◽  
Degrees Of Freedom ◽  
Control Method ◽  
Robot Manipulator ◽  
Impedance Control ◽  
Robot Manipulators ◽  
Compliant Motion ◽  
Stiffness Control

An active worktable, which can be applied to force control tasks of commercial robot manipulators, has been designed and built. The active worktable has several degrees of freedom and accommodates its position/force in accordance with the motion of a robot manipulator. A stiffness control method and an impedance control method are implemented in the active worktable to achieve compliant motion. Several experiments were carried out to confirm basic effectiveness of the active worktable.

Sign in / Sign up

Export Citation Format

Share Document