scholarly journals Adaptive Finite-Time Control for Formation Tracking of Multiple Nonholonomic Unmanned Aerial Vehicles with Quantized Input Signals

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Jinglin Hu ◽  
Xiuxia Sun ◽  
Lei He
Keyword(s):  
Finite Time ◽  
Tracking Error ◽  
Kinematic Model ◽  
Small Neighborhood ◽  
System Stability ◽  
Reference Trajectory ◽  
Input Quantization ◽  
Time Control ◽  
Formation Tracking ◽  
Multi Uav

Signal quantization can reduce communication burden in multiple unmanned aerial vehicle (multi-UAV) system, whereas it brings control challenge to formation tracking of multi-UAV system. This study presents an adaptive finite-time control scheme for formation tracking of multi-UAV system with input quantization. The UAV model contains nonholonomic kinematic model and autopilot model with uncertainties. The nonholonomic states of the UAVs are transformed by a transverse function method. For input quantization, hysteretic quantizers are used to reduce the system chattering and new decomposition is introduced to analyze the quantized signals. Besides, a novel transformation of the control signals is designed to eliminate the quantization effect. Based on the backstepping technique and finite-time Lyapunov stability theory, the adaptive finite-time controller is established for formation tracking of the multi-UAV system. Stability analysis proves that the tracking error can converge to an adjustable small neighborhood of the origin within finite time and all the signals in closed-loop system are semiglobally finite-time bounded. Simulation experiment illustrates that the system can track the reference trajectory and maintain the desired formation shape.

Finite-time tracking control for nonstrict-feedback nonlinear systems with unknown time delays and input saturation

2021 ◽  
pp. 014233122110583
Author(s):  
Xiaojing Qi ◽  
Wenhui Liu
Keyword(s):  
Finite Time ◽  
State Constraints ◽  
Tracking Error ◽  
Input Saturation ◽  
Small Neighborhood ◽  
Delay Systems ◽  
Fuzzy Logic Systems ◽  
Time Control ◽  
Full State ◽  
Full State Constraints

In this article, the problem of adaptive finite-time control is studied for a category of nonstrict-feedback nonlinear time-delay systems with input saturation and full state constraints. The fuzzy logic systems are applied to model the unknown nonlinear terms in the systems. Then, a novel tan-type barrier Lyapunov function is adopted to overcome the problem of full state constraints. By utilizing the finite-time control theory and the backstepping technique, a finite-time fuzzy adaptive controller is designed. The controller can guarantee that the tracking error is adjusted around zero with a small neighborhood in a finite time and all the signals in the closed-loop system are bounded. Finally, two simulation examples are included to verify the validity and feasibility of the control scheme.

Finite-time backstepping control with command filter for a class of nonlinear systems with parametric uncertainties

2020 ◽  
Vol 42 (12) ◽  
pp. 2297-2307 ◽  
Author(s):  
Cong Feng ◽  
Qing Wang ◽  
Changhua Hu ◽  
Shen Zhang
Keyword(s):  
Nonlinear Systems ◽  
Finite Time ◽  
Error Compensation ◽  
Tracking Error ◽  
Small Neighborhood ◽  
Backstepping Control ◽  
Parametric Uncertainties ◽  
Compensation Mechanism ◽  
Time Control ◽  
Command Filter

In this paper, the problem of adaptive finite-time control is considered for a class of nonlinear systems with parametric uncertainties. A novel adaptive command filtered backstepping control method is proposed, and the adverse impact caused by the command filter is eliminated by introducing modified error compensation mechanism with consideration of parametric uncertainties. Combined with the designed adaptation laws, the error compensation mechanism can be finite-time stable. Rigorous proof is achieved to show that the tracking error converges to a small neighborhood of zero in finite time with online parameters adaptation and error compensation. Finally, numeral simulations are presented to validate the effectiveness of the proposed adaptive finite-time control scheme.

Adaptive finite-time control for stochastic nonlinear systems using multi-dimensional Taylor network

2021 ◽  
pp. 014233122110396
Author(s):  
Shan-Liang Zhu ◽  
Ming-Xin Wang ◽  
Yu-Qun Han
Keyword(s):  
Nonlinear Systems ◽  
Finite Time ◽  
Tracking Error ◽  
Small Neighborhood ◽  
Lyapunov Stability Theory ◽  
Loop System ◽  
Stochastic Nonlinear Systems ◽  
Time Control ◽  
Control Scheme ◽  
The Stability

In this paper, the problem of adaptive finite-time multi-dimensional Taylor network (MTN) control for a class of stochastic nonlinear systems is investigated. By combining the MTN-based approximate method and adaptive backstepping technique, a novel adaptive finite-time MTN control scheme is proposed. In this scheme, the MTNs are used to approximate the unknown nonlinear functions of the systems. The finite-time Lyapunov stability theory is utilized to prove the stability of the close-loop system. The proposed scheme can ensure that all signals in the closed-loop system are bounded in probability and the tracking error converges to a small neighborhood of the origin in a finite time. Three simulation examples are presented to show the effectiveness of the control scheme. It should be pointed that the adaptive MTN controller proposed in this paper has the advantages of fast computational speed and good real-time performance thanks to the simple structure of the MTN.

ROBUST FINITE TIME CONTROLLER DESIGN FOR SECOND ORDER NONLINEAR UNDERACTUATED MECHANICAL SYSTEMS

2013 ◽  
Vol 37 (3) ◽  
pp. 549-557 ◽  
Author(s):  
Chi-Cheng Cheng ◽  
Kuang-Shine Yang ◽  
Jung-Hua Yang
Keyword(s):  
Lyapunov Stability ◽  
Finite Time ◽  
Controller Design ◽  
Tracking Error ◽  
Mechanical Systems ◽  
Second Order ◽  
System Stability ◽  
Underactuated Mechanical Systems ◽  
Pendulum System ◽  
Time Control

For a class of second order underactuated mechanical systems, a robust finite time control strategy is developed in this paper. The robust finite time controller is to drive the tracking error to be zero at the fixed final time. In order to assure system stability, we present a generalized Lyapunov stability proof for the second order underactuated mechanical system. By utilizing a Lyapunov stability theorem, we can achieve finite time tracking of desired reference signals for underactuated systems, which are subject to both external disturbances and system uncertainties. The proposed control scheme is demonstrated by actual experiments on a Furuta pendulum system.

scholarly journals Underactuated AUV Nonlinear Finite-Time Tracking Control Based on Command Filter and Disturbance Observer

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4987 ◽  
Author(s):  
Xu ◽  
Zhang ◽  
Cao ◽  
Pang ◽  
Sun
Keyword(s):  
Finite Time ◽  
Autonomous Underwater Vehicle ◽  
Tracking Error ◽  
Three Dimensional ◽  
Path Following ◽  
Lyapunov Stability Theory ◽  
Ocean Currents ◽  
3D Tracking ◽  
Time Control ◽  
Underactuated Auv

The three-dimensional (3D) path following problem of an underactuated autonomous underwater vehicle with ocean currents disturbances is addressed in this paper. Firstly, the motion equation under the ocean currents disturbance is established, and the dynamic model of 3D tracking error is constructed based on virtual guidance method. Then, a finite-time control scheme based on super-twisting observer and command filtered backstepping technology is proposed. We adopt super-twisting observer based on finite-time theory to observe the ocean currents disturbances for improving the system robust. A command filtered backstepping is proposed to replace the differential process in the conventional backstepping method for avoiding the differential expansion problem. The filter compensation loop is designed to ensure the accuracy of the filtered signal, and the anti-integration saturation link is designed considering the influence of integral saturation. Lyapunov stability theory is used to prove the stability of the underactuated AUV. Simulation studies are conducted to show the effectiveness and robustness of the controller.

scholarly journals Time-varying output formation-tracking of heterogeneous multi-agent systems with time-varying delays and switching topologies

2021 ◽  
Vol 54 (9-10) ◽  
pp. 1371-1382
Author(s):  
Shiyu Zhou ◽  
Yongzhao Hua ◽  
Xiwang Dong ◽  
Jianglong Yu ◽  
Zhang Ren
Keyword(s):  
Tracking Error ◽  
Lyapunov Theory ◽  
Reference Trajectory ◽  
Time Varying ◽  
Multi Agent Systems ◽  
Agent Systems ◽  
Switching Topologies ◽  
Formation Tracking ◽  
Multi Agent ◽  
Control Feedback

This paper focuses on the time-varying output formation (TVOF) tracking control of heterogeneous linear multi-agent systems (HL-MASs) with both delays and switching topologies, where the followers’ outputs can move along the reference trajectory generated by the leaders and maintain the desired time-varying formation. First, a distributed observer is proposed for each follower, aiming to estimate the convex combination of leaders’ state with both communication delays and switching graphs. The observer’s error for heterogeneous MASs is analyzed based on Lyapunov theory and linear matrix inequality (LMI) technique. Second, the observer is incorporated into the output formation tracking protocol. Then, an algorithm is put forward to calculate the control feedback gains and the formation tracking feasibility constraint is also provided. Furthermore, the convergence of the formation tracking error is proved. At last, the effectiveness of this proposed method is validated through a numerical simulation.

scholarly journals Adaptive Finite-Time Control on SE(3) for Spacecraft Final Proximity Maneuvers with Input Quantization

2021 ◽  
Vol 2021 ◽  
pp. 1-25
Author(s):  
Sai Zhang ◽  
Zhen Yang
Keyword(s):  
Finite Time ◽  
Tracking System ◽  
Integrated Control ◽  
External Disturbance ◽  
Uniform Motion ◽  
Input Quantization ◽  
Time Control ◽  
Control Precision ◽  
One Step ◽  
Rendezvous And Docking

In this paper, a bounded finite-time control strategy is developed for the final proximity maneuver of spacecraft rendezvous and docking exposed to external disturbance and input quantization. To realize the integrated control for spacecraft final proximity operation, the coupling kinematics and dynamics of attitude and position are modeled by feat of Lie group SE 3 . With a view to improving the convergence rate and reducing the chattering, an adaptive finite-time controller is proposed for the error tracking system with one-step theoretical proof of stability. Meanwhile, the hysteresis logarithmic quantizer is implemented to effectively reduce the frequency of data transmission and the quantization errors are reduced under the proposed controller. The algorithms outlined above are based on an integrated model expressed by SE 3 and denoted by uniform motion states, which can simplify the design progress and improve control precision. Finally, simulations are provided to exhibit the effectiveness and advantages of the designed strategy.

Adaptive finite-time tracking control for full state constrained nonlinear systems with time-varying delays and input saturation

2021 ◽  
pp. 014233122110658
Author(s):  
Tian Xu ◽  
Yuxiang Wu ◽  
Haoran Fang ◽  
Fuxi Wan
Keyword(s):  
Finite Time ◽  
Tracking Control ◽  
Tracking Error ◽  
Input Saturation ◽  
Time Derivative ◽  
Small Neighborhood ◽  
Constrained Systems ◽  
Design System ◽  
Time Varying ◽  
Full State

This paper investigates the adaptive finite-time tracking control problem for a class of nonlinear full state constrained systems with time-varying delays and input saturation. Compared with the previously published work, the considered system involves unknown time-varying delays, asymmetric input saturation, and time-varying asymmetric full state constraints. To ensure the state constraint satisfaction, the appropriate time-varying asymmetric Barrier Lyapunov Functions and the backstepping technique are utilized. Meanwhile, the finite covering lemma and the radial basis function neural networks are employed to solve the unknown time-varying delays. The assumption that the time derivative of time-varying delay functions is required to be less than one in traditional Lyapunov–Krasovskii functionals is removed by the proposed method. Moreover, the asymmetric input saturation is handled by an auxiliary design system. Taking the norm of the neural network weight vector as an adaptive parameter, a novel adaptive finite-time tracking controller with minimal learning parameters is constructed. It is proved that the proposed controller can guarantee that all signals in the closed-loop system are bounded, all states are constrained within the predefined sets, and the tracking error converges to a small neighborhood of the origin in a finite time. Finally, a comparison study simulation is given to demonstrate the effectiveness of our proposed strategy. The simulation results show that our proposed strategy has good advantages of high tracking precision and disturbance rejection.

Sign in / Sign up

Export Citation Format

Share Document