A Robust Inner and Outer Loop Control Method for Trajectory Tracking of a Quadrotor

Wheeled mobile robots (WMRs) in real complex environments such as on extraterrestrial planets are confronted with uncertain external disturbances and strong coupling of wheel-ground interactions while tracking commanded trajectories. Methods based on sliding mode control (SMC) are popular approaches for these situations. Traditional SMC has some potential problems, such as slow convergence, poor robustness, and excessive output chattering. In this paper, a kinematic-based feed-forward control model is designed for WMRs with longitudinal slippage and applied to the closed-loop control system for active compensation of time-varying slip rates. And a new adaptive SMC method is proposed to guide a WMR in trajectory tracking missions based on the kinematic model of a general WMR. This method combines the adaptive control method and a fast double-power reaching law with the SMC method. A complete control loop with active slip compensation and adaptive SMC is thus established. Simulation results show that the proposed method can greatly suppress chattering and improve the robustness of trajectory tracking. The feasibility of the proposed method in the real world is demonstrated by experiments with a skid-steered WMR on the loose-soil terrain.

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Research of Wind Power into the Grid Based on Large-Capacity Parallel Converter Modules

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.5899 ◽

2011 ◽

Vol 383-390 ◽

pp. 5899-5906

Author(s):

Fei Ye ◽

Zhong Dong Yin ◽

Chen Xin Dai

Keyword(s):

Control Method ◽

Power Grid ◽

Dead Zone ◽

Loop Current ◽

Parallel Operation ◽

Outer Loop ◽

Loop Control ◽

Three Phase ◽

The Dead ◽

Three Phase Inverter

The converters connected to the power grid, including rectifier and inverter. The rectifier uses DC voltage outer loop control method and the input current inner loop control method, three-phase inverter output current uses SPWM modulation. With the capacity of the system increasing, the capacity of a single converter can no longer meet the requirements, for improving the system's power grid, reliability and efficiency, converters can be paralleled. Parallel operation generates loop current; one of the effective methods of suppressing the loop current is to connect limiting inductance in the inverter AC side. Through simulation, gets the suitable inductance value, and researches the dead zone time affecting on the loop current. When the dead zone times of two modules are not equal, the loop current increases.

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A Control Strategy of a Single-phase H6-type Grid-connected Inverter with Low Harmonic Current

MATEC Web of Conferences ◽

10.1051/matecconf/201817302041 ◽

2018 ◽

Vol 173 ◽

pp. 02041

Author(s):

Lin Chunxu ◽

Zhou Chunhua ◽

Li Wei ◽

Chen Rui

Keyword(s):

Control Strategy ◽

Single Phase ◽

Closed Loop ◽

High Efficiency ◽

Control Method ◽

Harmonic Distortion ◽

Outer Loop ◽

Lcl Filter ◽

Loop Control ◽

Grid Connected Inverter

In order to reduce the total harmonic distortion (THD) of the grid-connected current caused by the high-frequency switching of the inverter, this paper combines the high efficiency single-phase H6-type inverter with LCL filter. The double closed-loop control method that consists of grid-connected current outer loop and capacitor current inner loop is put forward, by which a resonance peak of a low damping LCL filter is eliminated. In the grid-connected current outer loop, quasi proportion resonant (QPR) controller is adopted to overcome the steady-state error and weak anti-jamming capability in traditional PI controller. Finally, a simulation model is built in SIMULINK to verify the research. The simulation results show that, based on the single-phase H6-type inverter and LCL filter, the double closed-loop QPR control strategy can achieve the static error free tracking control of grid-connected current, which makes the system more stable and reduces the THD of grid-connected current effectively.

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Robust Global Trajectory Tracking for Underactuated VTOL Aerial Vehicles Using Inner-Outer Loop Control Paradigms

IEEE Transactions on Automatic Control ◽

10.1109/tac.2016.2557967 ◽

2017 ◽

Vol 62 (1) ◽

pp. 97-112 ◽

Cited By ~ 39

Author(s):

Roberto Naldi ◽

Michele Furci ◽

Ricardo G. Sanfelice ◽

Lorenzo Marconi

Keyword(s):

Trajectory Tracking ◽

Outer Loop ◽

Loop Control ◽

Aerial Vehicles ◽

Global Trajectory

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Dynamic Simulation for Grid-Connected Inverters of Distributed Generation Based on DIgSILENT Software

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.291-294.2042 ◽

2013 ◽

Vol 291-294 ◽

pp. 2042-2046

Author(s):

Zhang Le Zhao ◽

You Bing Zhang ◽

Jun Qi

Keyword(s):

Distributed Generation ◽

Control Strategy ◽

Control Method ◽

Control Strategies ◽

Simulation Models ◽

Double Loop ◽

Rotating Frame ◽

Control Methods ◽

Outer Loop ◽

Loop Control

This paper introduces some typical control methods for the grid-connected inverters in the distributed generation (DG) systems, the double-loop control strategy is focused on and analyzed in detail. The proposed outer-loop control strategies are summarized. Meanwhile, the inner-loop control method established on dq rotating frame is introduced. The simulation models of the inverters for DG in the DIgSILENT software are introduced, and the simulations for the proposed control strategies are realized.

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Performance of Outer-Loop Control for Adaptive Modulation and Coding Based on Mutual Information in OFDM MIMO SDM

IEICE Transactions on Communications ◽

10.1587/transcom.e98.b.1506 ◽

2015 ◽

Vol E98.B (8) ◽

pp. 1506-1517 ◽

Cited By ~ 1

Author(s):

Teppei EBIHARA ◽

Yasuhiro KUGE ◽

Hidekazu TAOKA ◽

Nobuhiko MIKI ◽

Mamoru SAWAHASHI

Keyword(s):

Mutual Information ◽

Adaptive Modulation ◽

Adaptive Modulation And Coding ◽

Outer Loop ◽

Loop Control

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An Efficient Approach for Modeling and Control of a Quadrotor

Wasit Journal of Engineering Sciences ◽

10.31185/ejuow.vol4.iss2.44 ◽

2016 ◽

Vol 4 (2) ◽

pp. 1-16

Author(s):

Ahmed S. Khusheef

Keyword(s):

Pid Control ◽

Control Method ◽

Mechanical Design ◽

Loop Control ◽

Modeling And Control ◽

Loop Control System ◽

And Control ◽

Close Loop Control ◽

Close Loop Control System ◽

Made In

A quadrotor is a four-rotor aircraft capable of vertical take-off and landing, hovering, forward flight, and having great maneuverability. Its platform can be made in a small size make it convenient for indoor applications as well as for outdoor uses. In model there are four input forces that are essentially the thrust provided by each propeller attached to each motor with a fixed angle. The quadrotor is basically considered an unstable system because of the aerodynamic effects; consequently, a close-loop control system is required to achieve stability and autonomy. Such system must enable the quadrotor to reach the desired attitude as fast as possible without any steady state error. In this paper, an optimal controller is designed based on a Proportional Integral Derivative (PID) control method to obtain stability in flying the quadrotor. The dynamic model of this vehicle will be also explained by using Euler-Newton method. The mechanical design was performed along with the design of the controlling algorithm. Matlab Simulink was used to test and analyze the performance of the proposed control strategy. The experimental results on the quadrotor demonstrated the effectiveness of the methodology used.

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Robust finite-time trajectory tracking control for a space manipulator with parametric uncertainties and external disturbances

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/09544100211014754 ◽

2021 ◽

pp. 095441002110147

Author(s):

Qijia Yao

Keyword(s):

Trajectory Tracking ◽

Finite Time ◽

Tracking Control ◽

Disturbance Observer ◽

Control Method ◽

Parametric Uncertainties ◽

External Disturbances ◽

Trajectory Tracking Control ◽

Space Manipulator ◽

Tracking Controller

Space manipulator is considered as one of the most promising technologies for future space activities owing to its important role in various on-orbit serving missions. In this study, a robust finite-time tracking control method is proposed for the rapid and accurate trajectory tracking control of an attitude-controlled free-flying space manipulator in the presence of parametric uncertainties and external disturbances. First, a baseline finite-time tracking controller is designed to track the desired position of the space manipulator based on the homogeneous method. Then, a finite-time disturbance observer is designed to accurately estimate the lumped uncertainties. Finally, a robust finite-time tracking controller is developed by integrating the baseline finite-time tracking controller with the finite-time disturbance observer. Rigorous theoretical analysis for the global finite-time stability of the whole closed-loop system is provided. The proposed robust finite-time tracking controller has a relatively simple structure and can guarantee the position and velocity tracking errors converge to zero in finite time even subject to lumped uncertainties. To the best of the authors’ knowledge, there are really limited existing controllers can achieve such excellent performance under the same conditions. Numerical simulations illustrate the effectiveness and superiority of the proposed control method.

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