Broad-RBFNN-Based Intelligence Adaptive Antidisturbance Formation Control for a Class of Cluster Aerospace Unmanned Systems with Multiple High-Dynamic Uncertainties

This paper investigates the antidisturbance formation control problem for a class of cluster aerospace unmanned systems (CAUSs) suffering from multisource high-dynamic uncertainties. Firstly, to estimate and compensate the uncertainties existing in CAUS coordinate dynamics, an adaptive antidisturbance formation control law, which is combined by a robust adaptive control law and the second order disturbance observer, has been designed. Secondly, aiming at the adverse influences caused by the nonlinear time-varying nonlinearities existing in the formation flight dynamics, the radial basis function neural network (RBFNN) is introduced. Furthermore, considering the rapidly varying characteristics of the aforementioned formation flight nonlinearities, a novel board RBFNN (B-RBFNN) has been constructed and utilized to improve the approximation and compensation performance. In virtue of the fusing of the B-RBFNN and the second-order disturbance observer-based adaptive formation control law, the rapid response rate and the higher control accuracy of the formation control system can be achieved. As a result, a novel B-RBFNN-based intelligence adaptive antidisturbance formation control algorithm has been established for CAUS trajectory coordination and formation flight. Numerical simulation results are proposed to illustrate the effectiveness and advantages of the proposed B-RBFNN-based intelligent adaptive formation control method for the CAUS.

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High-Order Disturbance Observer-Based Neural Adaptive Control for Space Unmanned Systems with Stochastic and High-dynamic Uncertainties

IEEE Access ◽

10.1109/access.2021.3083567 ◽

2021 ◽

pp. 1-1

Author(s):

Yao Zhang ◽

Xin Ning ◽

Zheng Wang ◽

Dengxiu Yu

Keyword(s):

Adaptive Control ◽

Disturbance Observer ◽

High Order ◽

Unmanned Systems ◽

Neural Adaptive Control ◽

High Dynamic ◽

Dynamic Uncertainties

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Robust adaptive tracking control for uncertain nonholonomic mobile manipulator

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

10.1177/09596518211027716 ◽

2021 ◽

pp. 095965182110277

Author(s):

Abdelkrim Brahmi ◽

Maarouf Saad ◽

Brahim Brahmi ◽

Ibrahim El Bojairami ◽

Guy Gauthier ◽

...

Keyword(s):

Control Method ◽

Sliding Mode ◽

Robust Adaptive Control ◽

Convergence Time ◽

Adaptive Sliding Mode Control ◽

Mobile Manipulator ◽

Control Law ◽

Adaptive Tracking Control ◽

Robust Adaptive ◽

Manipulator Robot

In the research put forth, a robust adaptive control method for a nonholonomic mobile manipulator robot, with unknown inertia parameters and disturbances, was proposed. First, the description of the robot’s dynamics model was developed. Thereafter, a novel adaptive sliding mode control was designed, to which all parameters describing involved uncertainties and disturbances were estimated by the adaptive update technique. The proposed control ensures a relatively good system tracking, with all errors converging to zero. Unlike conventional sliding mode controls, the suggested is able to achieve superb performance, without resulting in any chattering problems, along with an extremely fast system trajectories convergence time to equilibrium. The aforementioned characteristics were attainable upon using an innovative reaching law based on potential functions. Furthermore, the Lyapunov approach was used to design the control law and to conduct a global stability analysis. Finally, experimental results and comparative study collected via a 05-DoF mobile manipulator robot, to track a given trajectory, showing the superior efficiency of the proposed control law.

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A novel second-order sliding mode control based on the Lyapunov method

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331218783244 ◽

2018 ◽

Vol 41 (4) ◽

pp. 1068-1078 ◽

Cited By ~ 1

Author(s):

Lu Liu ◽

Shihong Ding ◽

Li Ma ◽

Haibin Sun

Keyword(s):

Sliding Mode Control ◽

Finite Time ◽

Disturbance Observer ◽

Control Method ◽

Sliding Mode ◽

Second Order ◽

Lyapunov Theory ◽

Mode Control ◽

Mismatched Disturbance ◽

Second Order Sliding Mode

In this paper, a novel discontinuous second-order sliding mode control approach has been developed to handle sliding mode dynamics with a nonvanishing mismatched disturbance by using Lyapunov theory and a finite-time disturbance observer. Firstly, the finite-time disturbance observer is designed to estimate the nonvanishing mismatched disturbance. Secondly, a virtual controller has been constructed based on the estimated value such that the sliding variable can be stabilized to zero in a finite time. Then, the real discontinuous controller is designed to guarantee that the virtual controller can be well tracked in a finite time. Lyapunov analysis also verifies the finite-time stability of the closed-loop sliding mode control system. The developed discontinuous second-order sliding mode control method possesses two appealing features including strong robustness with respect to the matched and mismatched nonvanishing disturbances, and relaxation on the constant upper bound of uncertainties widely used in a conventional second-order sliding mode. Finally, an academic example is illustrated to verify the effectiveness of the proposed method.

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Adaptive smooth second-order sliding mode control method with application to missile guidance

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331215621616 ◽

2015 ◽

Vol 39 (6) ◽

pp. 848-860 ◽

Cited By ~ 10

Author(s):

Zheng Wang

Keyword(s):

Sliding Mode Control ◽

Finite Time ◽

Control Method ◽

Sliding Mode ◽

Second Order ◽

Control Law ◽

Smooth Control ◽

Mode Control ◽

Control Command ◽

Second Order Sliding Mode

This paper proposes an adaptive smooth second-order sliding mode control law for a class of uncertain non-linear systems. The key point of this control law is ensuring a smooth control signal considering parametric uncertainty and disturbances with unknown bounds. The proposed control method is obtained by introducing a continuous function under the integral and using adaptive gains. The switching function and its derivative are forced to zero in finite time. This is achieved using a smooth control command and without the prior knowledge of upper bound parameters of uncertainties. The finite-time stability is proved based on a quadratic Lyapunov approach and the reaching time is estimated. This structure is used to create a homing guidance law and the efficiency is evaluated via simulations.

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Fixed-Time Formation Control for Second-Order Disturbed Multi-Agent Systems under Directed Graph

Symmetry ◽

10.3390/sym13122295 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2295

Author(s):

Huifen Hong ◽

He Wang

Keyword(s):

Formation Control ◽

Control Method ◽

Variable Structure ◽

Fixed Time ◽

Second Order ◽

Multi Agent Systems ◽

Structure Control ◽

Agent Systems ◽

Bounded Disturbances ◽

Multi Agent

This paper investigates the fixed-time formation (FixF) control problem for second-order multi-agent systems (MASs), where each agent is subject to disturbance and the communication network is general directed. First, a FixF protocol is presented based on the backstepping technique, where the distributed cooperative variable structure control method is utilized to handle the bounded disturbances. Then, to remove the dependence of control gains on the global information, a practical adaptive FixF control is presented, where the MASs can achieve formation with a bounded error within fixed time. Finally, a numerical example is presented to validate the theoretical result.

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Practical Formation Control for Multiple Anonymous Robots System with Unknown Nonlinear Disturbances

Applied Sciences ◽

10.3390/app11199170 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9170

Author(s):

Peng Xu ◽

Jin Tao ◽

Minyi Xu ◽

Guangming Xie

Keyword(s):

Theoretical Analysis ◽

Mobile Robots ◽

Distributed Control ◽

Formation Control ◽

Control Method ◽

Control Law ◽

Control Problems ◽

Moving Target ◽

Whole Process ◽

Nonlinear Disturbances

This paper mainly investigates formation control problems for a group of anonymous mobile robots with unknown nonlinear disturbances on a plane, in which all robots can asymptotically converge to any formation patterns without collision, and maintain any required relative distance with neighboring robots. To solve this problem, all robots are modeled as kinematic points and can only acquire information from other robots and their targets. Furthermore, a flexible distributed control law is designed to solve the formation problem while no collisions between any robots can be guaranteed during the whole process. The outstanding feature of the proposed control method is that it can force all mobile robots to form not only uniform circle formations but also non-uniform and non-circular formations with moving target centers. At last, both theoretical analysis and numerical simulations show the feasibility of the proposed control law.

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Dynamic Event-Triggered Time-Varying Formation Control of Second-Order Dynamic Agents: Application to Multiple Quadcopters Systems

Applied Sciences ◽

10.3390/app10082814 ◽

2020 ◽

Vol 10 (8) ◽

pp. 2814 ◽

Cited By ~ 2

Author(s):

Anh Tung Nguyen ◽

Thanh Binh Nguyen ◽

Sung Kyung Hong

Keyword(s):

Formation Control ◽

Second Order ◽

Formation Flight ◽

Time Varying ◽

Triggering Mechanism ◽

Agent Based ◽

Dynamic Event ◽

Event Triggering ◽

Communication Ability ◽

Event Triggered

This paper investigates the problem of the time-varying formation control of a second-order dynamic agent based on a distributed dynamic event-triggered algorithm. In this problem, each agent can exchange the information of its position and velocity with its neighbors via limited communication ability. Our approach provides a new dynamic event triggering mechanism to reduce the number of triggering times while maintaining satisfactory control performance. Further, a novel Lyapunov function is proposed to guarantee that the group of agents asymptotically tracks the desired time-varying formation trajectory. The practical applicability of the event triggering mechanism is also indicated by excluding the Zeno behavior in the proposed control algorithm. Finally, the validity and effectiveness of the proposed method are demonstrated via illustrative examples of the time-varying formation flight for six quadcopters.

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Formation control for multi-UAVs systems based on Kullback-Leibler divergence

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331219878581 ◽

2019 ◽

Vol 42 (3) ◽

pp. 598-603

Author(s):

Wei Liao ◽

Xiaohui Wei ◽

Jizhou Lai ◽

Hao Sun

Keyword(s):

Formation Control ◽

Control Method ◽

Initial Conditions ◽

Dimensional Space ◽

Three Dimensional ◽

Initial Position ◽

Probability Density Functions ◽

Control Law ◽

Leibler Divergence ◽

Three Dimensional Space

This paper presents a formation control method for multi unmanned aerial vehicles (UAVs) systems. The first step is to design two probability density functions describing to the desired formation and current formation, respectively. Then, through minimizing the Kullback-Leibler divergence, this method is able to bring the UAVs to a desired formation and stabilizes the desired formation in all initial conditions except the case where a pair of UAVs are in the same initial position. The gradient of Kullback-Leibler divergence is calculated using Monte Carlo method, by means of which it is not necessary to preplan route for every UAV and to take extra measure to avoid collisions between any two UAVs during the motion. At the end of this paper, the proposed method is adopted to carry out to some numerical simulations in a two-dimensional space and a three-dimensional space, respectively, to illustrate the effectiveness of the method. Conclusions show that the formation of the UAVs can converge to the desired formation under the control law proposed in this paper.

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A Robust Adaptive Sliding Mode Control Method for Attitude Control of the Quad-Rotor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.852.391 ◽

2014 ◽

Vol 852 ◽

pp. 391-395

Author(s):

Yong Gao ◽

Zhao Qing Song ◽

Xiao Liu

Keyword(s):

Attitude Control ◽

Control Method ◽

Sliding Mode ◽

Tracking Error ◽

Robust Adaptive Control ◽

Adaptive Sliding Mode Control ◽

Control Law ◽

Unknown Disturbances ◽

Robust Adaptive ◽

Uncertainty Parameters

Quad-rotor is a multi-variable and strong coupling system which has nonlinear and uncertainties. According to the quad-rotor, a dynamic model of attitude which included uncertainty parameters and unknown disturbances was established. The tracking error state was used to design a slide mode surface, and a Lyapunov function which includes slide mode surface and unknown parameter was built. Further more, a robust adaptive control law was designed. At last, the designed control law was simulated, and the results justify the feasibility of the proposed control law.

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