Robust Output Feedback Control of Single-Link Flexible-Joint Robot Manipulator with Matched Disturbances Using High Gain Observer

Ullah, Hameed; Malik, Fahad Mumtaz; Raza, Abid; Mazhar, Naveed; Khan, Rameez; Saeed, Ahmad; Ahmad, Irfan

doi:10.3390/s21093252

Cited by 20 publications

(17 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In comparison with PFTC, AFTC provides outstanding performance when feedback information of faults from the FD is provided correctly. Therefore, some observers have been proposed for fault diagnosis to obtain higher exact information of the faults, such as high-gain observers [ 11 , 12 ], neural network observers [ 13 , 14 ], sliding mode observers (SMOs) [ 15 , 16 ], higher-order sliding mode observers (HOSMOs) [ 17 , 18 , 19 ], fuzzy logic observers [ 20 , 21 ], disturbance observers [ 22 , 23 , 24 , 25 ], etc. To provide accurate and timely fault information, the convergence of observers needs to be ensured within finite time.…”

Section: Introductionmentioning

confidence: 99%

A Novel Active Fault-Tolerant Tracking Control for Robot Manipulators with Finite-Time Stability

Truong

Van

2021

Sensors

View full text Add to dashboard Cite

Many terminal sliding mode controllers (TSMCs) have been suggested to obtain exact tracking control of robotic manipulators in finite time. The ordinary method is based on TSMCs that secure trajectory tracking under the assumptions such as the known robot dynamic model and the determined upper boundary of uncertain components. Despite tracking errors that tend to zero in finite time, the weakness of TSMCs is chattering, slow convergence speed, and the need for the exact robot dynamic model. Few studies are handling the weakness of TSMCs by using the combination between TSMCs and finite-time observers. In this paper, we present a novel finite-time fault tolerance control (FTC) method for robotic manipulators. A finite-time fault detection observer (FTFDO) is proposed to estimate all uncertainties, external disturbances, and faults accurately and on time. From the estimated information of FTFDO, a novel finite-time FTC method is developed based on a new finite-time terminal sliding surface and a new finite-time reaching control law. Thanks to this approach, the proposed FTC method provides a fast convergence speed for both observation error and control error in finite time. The operation of the robot system is guaranteed with expected performance even in case of faults, including high tracking accuracy, small chattering behavior in control input signals, and fast transient response with the variation of disturbances, uncertainties, or faults. The stability and finite-time convergence of the proposed control system are verified that they are strictly guaranteed by Lyapunov theory and finite-time control theory. The simulation performance for a FARA robotic manipulator proves the proposed control theory’s correctness and effectiveness.

show abstract

Section: Introductionmentioning

confidence: 99%

A Novel Active Fault-Tolerant Tracking Control for Robot Manipulators with Finite-Time Stability

Truong

Van

2021

Sensors

View full text Add to dashboard Cite

show abstract

“…However, these observer-based controls only ensure asymptotic stability. In addition, there are a few more proposed observers, such as the high-gain observer (HGO) [30] and the third-order sliding mode observer (TOSMO) [31]. While HGO only ensures asymptotic convergence in the study [30], the proof of finite-time convergence has not been fully yielded in the study [31].…”

Section: Introductionmentioning

confidence: 99%

“…In addition, there are a few more proposed observers, such as the high-gain observer (HGO) [30] and the third-order sliding mode observer (TOSMO) [31]. While HGO only ensures asymptotic convergence in the study [30], the proof of finite-time convergence has not been fully yielded in the study [31]. The Kalman filter (KF) is one of the most extensively applied approaches for monitoring and estimation.…”

Section: Introductionmentioning

confidence: 99%

“…If the control torques of FxNTSMC are designed for robot manipulators (1) based on the proposed FxNTSM Surface in Equation (11) and the proposed FxDO in Equation(24) which is given in Equation (30) then the proposed controller offers global fixed-time stability for robot manipulators. Inserting the control input(30) into Equation (29) obtains . s = γΦ −K|s| β sign(s) − Bsign(s) − δ 1 .…”

mentioning

confidence: 99%

See 1 more Smart Citation

A Robust Observer-Based Control Strategy for n-DOF Uncertain Robot Manipulators with Fixed-Time Stability

Truong

Kang

et al. 2021

Sensors

View full text Add to dashboard Cite

In this paper, a robust observer-based control strategy for n-DOF uncertain robot manipulators with fixed-time stability was developed. The novel fixed-time nonsingular sliding mode surface enables control errors to converge to the equilibrium point quickly within fixed time without singularity. The development of the novel fixed-time disturbance observer based on a uniform robust exact differentiator also allows uncertain terms and exterior disturbances to be proactively addressed. The designed observer can accurately approximate uncertain terms within a fixed time and contribute to significant chattering reduction in the traditional sliding mode control. A robust observer-based control strategy was formulated, according to a combination of the fixed-time nonsingular terminal sliding mode control method and the designed observer, to yield global fixed time stability for n-DOF uncertain robot manipulators. The proposed controller proved definitively that it was able to obtain global stabilization in fixed time. The approximation capability of the proposed observer, the convergence of the proposed sliding surface, and the effectiveness of the proposed control strategy in fixed time were fully confirmed by simulation performance on an industrial robot manipulator.

show abstract

“…However, the flexible manipulator is uncertain and nonlinear, due to the change of terminal load, the hysteresis of driving joint, the flexibility of link and other reasons, it is difficult to establish an accurate real-time model of the flexible manipulator. In order to overcome this problem, sliding mode control (Ullah et al, 2021), robust control (Yang et al, 2019), neural networks control (Gao et al, 2019), fuzzy control (Ethem et al, 2019; Ozguney and Burkan, 2021), and other intelligent control methods (Rahimi and Nazemizadeh, 2014) had achieved certain control effect in theory and application, but there are still many problems, such as large computation, difficult real-time guarantee, parameter drift, and chattering phenomenon. Adaptive control adjusts the control parameters online according to the system state feedback information, which is widely used in the position and vibration control of flexible manipulator (Pradhan and Subudhi, 2014; Schnelle and Eberhard, 2017; Zhang and Liu, 2013).…”

Section: Introductionmentioning

confidence: 99%

Hybrid control of piezoelectric flexible manipulator based on Volterra filtered-xLMS algorithm

Yang

Zhang

2021

Journal of Vibration and Control

View full text Add to dashboard Cite

To suppress the nonlinear vibration of the flexible manipulator during motion, this article presents a hybrid control strategy based on a servo motor and a piezoelectric actuator. The dynamic model of the piezoelectric flexible manipulator is established first. To realize the trajectory tracking, a proportional derivative control method is used to schedule the control torque. Because the Volterra filter can approximate the nonlinear system model, a Volterra filtered-xLMS algorithm based on a second-order Volterra filter structure is proposed, by which the active nonlinear vibration control of flexible link is realized. Simulation results show that the proposed Volterra filtered-xLMS algorithm can not only make use of the advantages of the classical filtered-xLMS algorithm but also solve the problem of effective modeling of nonlinear secondary path. The proposed hybrid control strategy based on Volterra filtered-xLMS algorithm and proportional derivative control algorithm can improve the position accuracy of joint and effectively suppress the vibration response of the nonlinear flexible link. A piezoelectric flexible manipulator with PZT (lead zirconate titanate) sensor and actuator is designed to demonstrate the validity and efficiency of the proposed method by experiments. Experiment results demonstrate that the attenuation time of vibration response is reduced from 5 s to 1.5 s, the vibration response at the first-order frequency is reduced by 60%, and the proposed methodology has an important advantage in application of active vibration control of piezoelectric flexible manipulator.

show abstract

Robust Output Feedback Control of Single-Link Flexible-Joint Robot Manipulator with Matched Disturbances Using High Gain Observer

Cited by 20 publications

References 56 publications

A Novel Active Fault-Tolerant Tracking Control for Robot Manipulators with Finite-Time Stability

A Novel Active Fault-Tolerant Tracking Control for Robot Manipulators with Finite-Time Stability

A Robust Observer-Based Control Strategy for n-DOF Uncertain Robot Manipulators with Fixed-Time Stability

Hybrid control of piezoelectric flexible manipulator based on Volterra filtered-xLMS algorithm

Contact Info

Product

Resources

About