High accuracy disturbance observer-based agile attitude stabilization with three-dimensional MSW

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Javad Tayebi ◽  
Chao Han ◽  
Yuanjin Yu
Keyword(s):  
Attitude Control ◽  
High Frequency ◽  
Disturbance Observer ◽  
Three Dimensional ◽  
High Accuracy ◽  
The Novel ◽  
Content Type ◽  
Attitude Stabilization ◽  
Steering Law ◽  
Long Lifetime

Purpose The purpose of this paper is agile attitude control design with the novel three-dimensional (3D) magnetically suspended wheel (MSW) that is the preferred type for agile maneuvering compared to conventional control moment gyro due to frictionless, low vibration and long lifetime. This system does not require a separate steering law for pyramid arrangement to derive tilt angles. It is also conducting an agile maneuver with high accuracy despite the high-frequency disturbances. Design/methodology/approach In this paper, a disturbance observer-based attitude stabilization method is proposed for an agile satellite with a pyramid cluster of the novel 3D magnetically suspended wheel actuator. This strategy includes a disturbance observer and a linear quadratic regulator controller. The rotor shaft deflection of MSW is actively controlled to reduce vibration and producing gyro torque. The deflection angle of the pyramid cluster MSWs considered as control parameters. The closed-loop stability is proved by using the Lyapunov strategy. The efficiency and performance of the offered method verified by numerical simulation via MATLAB/SIMULINK software. Findings According to simulation results, the disturbance observer-based control controller stabilized the system with high accuracy and optimal tilt angles without any extra steering law equation. Hence, the system speed is increased, and the system error is minimized without separate steering law. Practical implications The magnetically suspended wheel is a new kind of inertia actuator for attitude control that has several benefits such as frictionless, high-speed rotor, clean environment and low vibration compared to the traditional wheel. It has complex nonlinear dynamics that cause have complicated controller design. The proposed strategy stabilizes the system and conducting an agile maneuver with high precision despite the high-frequency disturbances. It is applicable for some missions requiring high accuracies, like Earth observation and the solar observation mission that require a very accurate pointing control and a long lifetime. Originality/value This paper is the initial paper to design a pyramid array for magnetically suspended wheels. Compared to other research, this method doesn’t need a separate steering law of the MSWs cluster and presented optimal tilt angles with less computational. Also, it designs a disturbance observer-based controller for this system that proposed high accuracy and agile stabilization.

Super-twisting disturbance observer-based finite- time attitude stabilization of flexible spacecraft subject to complex disturbances

2018 ◽  
Vol 25 (5) ◽  
pp. 1008-1018 ◽  
Author(s):  
Ruidong Yan ◽  
Zhong Wu
Keyword(s):  
Attitude Control ◽  
Disturbance Observer ◽  
Sliding Mode ◽  
State Variables ◽  
Attitude Dynamics ◽  
Attitude Control System ◽  
Terminal Sliding Mode ◽  
Nonlinear Disturbance Observer ◽  
Attitude Stabilization ◽  
Nonsingular Terminal Sliding Mode

There exist complex disturbances in the attitude control system of flexible spacecrafts, such as space environmental disturbances, flexible vibrations, inertia uncertainties, payload motions, etc. To suppress the effects of these disturbances on the performance of attitude stabilization, a super-twisting disturbance observer (STDO)-based nonsingular terminal sliding mode controller (NTSMC) is proposed in this paper. First, STDO is designed for a second-order dynamical system constructed by applying the lumped disturbance and its integral as state variables, and applying the integral as virtual measurement. Since the virtual measurement is obtained by integrating the inverse attitude dynamics, STDO not only avoids the differential operation of angular velocity, but also fully utilizes the information of a nonlinear model. By combining STDO with NTSMC, a composite controller is designed to achieve high-accuracy spacecraft attitude stabilization. Since most of the disturbances are compensated for by a STDO-based feedforward compensator, only a small switching gain is required to deal with the residual disturbances and uncertainties. Thus, the chattering phenomenon of the controller can be alleviated to a great extent. Finally, numerical simulations for the comparison between STDO-based NTSMC and nonlinear disturbance observer-based NTSMC are carried out in the presence of complex disturbances to verify the effectiveness of the proposed approach.

Enhanced disturbance observer-based robust yaw servo control for ROVs with multi-vector propulsion

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yihui Gong ◽  
Lin Li ◽  
Shengbo Qi ◽  
Changbin Wang ◽  
Dalei Song
Keyword(s):  
Attitude Control ◽  
Disturbance Observer ◽  
External Disturbance ◽  
Proportional Integral Derivative ◽  
Content Type ◽  
Proportional Integral ◽  
Control Scheme ◽  
Yaw Attitude ◽  
Nonlinear Hydrodynamics ◽  
Parameters Perturbation

Purpose A novel proportional integral derivative-extended state disturbance observer-based control (PID-ESDOBC) algorithm is proposed to solve the nonlinear hydrodynamics, parameters perturbation and external disturbance in yaw control of remote operated vehicles (ROVs). The effectiveness of PID-ESDOBC is verified through the experiments and the results indicate that the proposed method can effectively track the desired attitude and attenuate the external disturbance. Design/methodology/approach This study fully investigates the hydrodynamic model of ROVs and proposes a control-oriented hydrodynamic state space model of ROVs in yaw direction. Based on this, this study designs the PID-ESDOBC controller, whose stability is also analyzed through Kharitonov theorem and Mikhailov criterion. The conventional proportional-integral-derivative (PID) and active disturbance rejection control (ADRC) are compared with our method in our experiment. Findings In this paper, the authors address the nonlinear hydrodynamics, parameters perturbation and external disturbance problems of ROVs with multi-vector propulsion by using PID-ESDOBC control scheme. The advantage is that the nonlinearities and external disturbance can be estimated accurately and attenuate promptly without requiring the precise model of ROVs. Compared to PID and ADRC, both in overshoot and settling time, the improvement is 2X on average compared to conventional PID and ADRC in the pool experiment. Research limitations/implications The delays occurred in the control process can be solved in the future work. Practical implications The attitude control is a kernel problem for ROVs. A precise kinematic and dynamic model for ROVs and an advanced control system are the key factors to obtain the better maneuverability in attitude control. The PID-ESDOBC method proposed in this paper can effectively attenuate nonlinearities and external disturbance, which leads to a quick response and good tracking performance to baseline controller. Social implications The PID-ESDOBC algorithm proposed in this paper can be ensure the precise and fast maneuverability in attitude control of ROVs or other underwater equipment operating in the complex underwater environment. In this way, the robot can better perform undersea work and tasks. Originality/value The dynamics of the ROV and the nominal control model are investigated. A novel control scheme PID-ESDOBC is proposed to achieve rapidly yaw attitude tracking and effectively reject the external disturbance. The robustness of the controller is also analyzed which provides parameters tuning guidelines. The effectiveness of the proposed controller is experimental verified with a comparison by conventional PID, ADRC.

Effects of plasma nitriding interlayer on adhesion and tribological behaviors of AlTiSiN coating

2021 ◽  
Vol 73 (6) ◽  
pp. 945-953
Author(s):  
Mengjuan Yin ◽  
Wenping Liang ◽  
Qiang Miao ◽  
Shiwei Zuo ◽  
Haiyang Yu ◽  
...  
Keyword(s):  
Plasma Nitriding ◽  
Three Dimensional ◽  
Wear Property ◽  
The Novel ◽  
Content Type ◽  
The Matrix ◽  
Narrow Width ◽  
Glow Plasma ◽  
Excellent Adhesion ◽  
Ta15 Alloy

Purpose This study aims to the service life of TA15 alloy by solving the problem of the binding force between the matrix and AlTiSiN coating. The effect of a plasma nitriding (PN) interlayer on the magnetron-sputtered AlTiSiN coating was also investigated in detail. Design/methodology/approach The double-glow plasma alloying (DGPA) and magnetron sputtering (MS) techniques were combined as a new approach to realize a bilayer on TA15 consisting of an AlTiSiN layer with a PN interlayer. A TiN interlayer was formed via co-diffusion during the PN conducted at 1050°C for 3 h. Findings The PN interlayer can effectively improve the adhesion between coating and matrix; the PN/AlTiSiN coating presented excellent adhesion (80.1 N) and anti-wear property with a nano-hardness of 18.62 GPa. The resulting three-dimensional wear-track morphology exhibited a shallow depth and a narrow width. Originality/value The novel combination of the DGPA and MS technologies, using an infiltration layer rather than a coating one as the intermediate layer, can effectively enhance the adhesion between AlTiSiN coating and TA15 matrix. Meanwhile, the gradient layer can effectively improve both surface bearing and wear resistance.

A composite anti-disturbance control scheme for attitude stabilization and vibration suppression of flexible spacecrafts

2015 ◽  
Vol 23 (15) ◽  
pp. 2470-2477 ◽  
Author(s):  
Zhen Wang ◽  
Zhong Wu ◽  
Lijun Li ◽  
Jun Yuan
Keyword(s):  
Attitude Control ◽  
Disturbance Observer ◽  
Vibration Suppression ◽  
Disturbance Attenuation ◽  
Pd Controller ◽  
Parameter Uncertainties ◽  
Performance Simulation ◽  
Attitude Stabilization ◽  
Multiple Disturbances ◽  
Control Scheme

Abstract: There exist multiple disturbances resulting from the structural vibrations of flexible appendages, unknown external and internal disturbances, and parameter uncertainties, which affect the attitude control performance seriously. To enhance the disturbance attenuation performance and vibration suppression ability, a composite anti-disturbance control scheme (CADCS) based on disturbance observer is proposed for attitude stabilization and vibration reduction of flexible spacecraft. The CADCS combines a composite disturbance observer (CDO) and a PD controller with feedforward. The multiple disturbances are equivalent to slowly varying disturbance and harmonic disturbance. The CDO can estimate two types of disturbance and compensate for them through feedforward. The PD controller realizes the asymptotic convergence by compensating the disturbance from CDO. The CADCS based on CDO and PD controller is not only simple and easy to realize, but also yields better vibration suppression and anti-disturbance performance. Simulation results of a certain spacecraft demonstrate the effectiveness of the proposed CADCS.

scholarly journals 2D electrostatic modeling of twisted pairs

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kaoutar Hazim ◽  
Guillaume Parent ◽  
Stéphane Duchesne ◽  
Andrè Nicolet ◽  
Christophe Geuzaine
Keyword(s):  
Design Methodology ◽  
Three Dimensional ◽  
High Accuracy ◽  
Electrical Machines ◽  
Computational Time ◽  
Two Dimensional ◽  
Weak Formulation ◽  
Content Type ◽  
Twisted Pair ◽  
Electrostatic Modeling

Purpose This paper aims to model a three-dimensional twisted geometry of a twisted pair studied in an electrostatic approximation using only two-dimensional (2D) finite elements. Design/methodology/approach The proposed method is based on the reformulation of the weak formulation of the electrostatics problem to deal with twisted geometries only in 2D. Findings The method is based on a change of coordinates and enables a faster computational time as well as a high accuracy. Originality/value The effectiveness of the adopted approach is demonstrated by studying different configurations related to the IEC 60851-5 standard defined for the measurement of the electrical properties of the insulation of the winding wires used in electrical machines.

scholarly journals Digital Design of a Universal Rat Intraoral Device for Therapeutic Evaluation of a Topical Formulation against Candida-Associated Denture Stomatitis

2019 ◽  
Vol 87 (12) ◽  
Author(s):  
Ahmed S. Sultan ◽  
Alexandra M. Rizk ◽  
Taissa Vila ◽  
Yadong Ji ◽  
Radi Masri ◽  
...  
Keyword(s):  
Oral Candidiasis ◽  
Three Dimensional ◽  
Opportunistic Pathogen ◽  
Digital Design ◽  
The Novel ◽  
Topical Formulation ◽  
Content Type ◽  
Denture Stomatitis ◽  
Intraoral Device ◽  
Technological Advances

ABSTRACT Candida-associated denture stomatitis (DS) is a persistent and chronic oral infection of the denture-bearing palatal mucosa. DS stems from the ability of the fungal opportunistic pathogen Candida albicans to adhere to denture material and invade palatal tissue. Although DS is the most prevalent form of oral candidiasis, there are currently no feasible therapeutic strategies for the prevention of this recurrent condition. We developed a peptide-based antimicrobial bioadhesive formulation specifically designed for oral topical formulation. In this study, we aimed to evaluate the applicability of the novel formulation for the prevention of C. albicans colonization on denture material and development of clinical disease. To that end, using the latest technological advances in dental digital design and three-dimensional (3D) printing, we fabricated an intraoral device for rats with universal fit. The device was successfully installed and used to develop clinical DS. Importantly, by taking a preventative therapeutic approach, we demonstrated the potential clinical utility of the novel formulation as a safe and feasible prophylactic agent against DS.

Disturbance observer-based coordinated control for three dimensional formation of unmanned autonomous helicopter

2019 ◽  
Vol 40 (1) ◽  
pp. 155-162
Author(s):  
Rong Mei
Keyword(s):  
Disturbance Observer ◽  
Sliding Mode ◽  
Three Dimensional ◽  
Coordinated Control ◽  
Lyapunov Theory ◽  
Formation Flight ◽  
Time Varying ◽  
Content Type ◽  
Sliding Mode Disturbance Observer ◽  
Autonomous Helicopter

Purpose This paper aims to study the issue of the three-dimensional formation coordinated control for the unmanned autonomous helicopter (UAH) by using the sliding mode disturbance observer. Under the designed formation coordinated controller, the desired formation can be maintained and the closed-loop system stability is analyzed by using the Lyapunov theory. Design/methodology/approach Considering the unknown time-varying external 10; disturbance in formation flight of UAHs, a sliding mode disturbance observer has been employed to estimate them. Findings This work is supported in part by the National Natural Science Foundation of China under Grant 61803207, and in part by the Fundamental Research Funds for the Central Universities under Grant LGZD201806. Originality/value A sliding mode disturbance observer has been designed to estimate the unknown time-varying external disturbance in formation flight of UAHs. Aiming at the leading UAH maneuver in three-dimensional space during the formation flight progress, the formation coordinated controller has been proposed based on the output of the disturbance observer to maintain the formation.

Stabilization and circuit implementation of a novel chemical oscillating chaotic system

Circuit World ◽  
2019 ◽  
Vol 45 (2) ◽  
pp. 93-106
Author(s):  
Li Xiong ◽  
Wanjun Yin ◽  
Xinguo Zhang
Keyword(s):  
Chaotic System ◽  
Control Method ◽  
Three Dimensional ◽  
Chaotic Attractors ◽  
The Novel ◽  
Content Type ◽  
Initial Values ◽  
Parameters Selection ◽  
Chaotic Circuits ◽  
Simulation Results

Purpose This paper is aimed at investigating a novel chemical oscillating chaotic system with different attractors at fixed parameters. The typical dynamical behavior of the new chemical oscillating system is discussed, and it is found that the state selection is dependent on initial values. Then, the stabilization problem of the chemical oscillating attractors is investigated analytically and numerically. Subsequently, the novel electronic circuit of the proposed chemical oscillating chaotic system are constructed, and the influences of the changes of circuit parameters on chemical oscillating chaotic attractors are investigated. Design/methodology/approach The different attractors of the novel chemical oscillating chaotic system are investigated by changing the initial values under fixed parameters. Moreover, the active control and adaptive control methods are presented to make the chemical oscillating chaotic systems asymptotically stable at the origin based on the Lyapunov stability theory. The influences on chemical oscillating chaotic attractors are also verified by changing the circuit parameters. Findings It is found that the active control method is easier to be realized by using physical components because of its less control signal and lower cost. It is also confirmed that the adaptive control method enjoys strong anti-interference ability because of its large number of selected controllers. What can be seen from the simulation results is that the chaotic circuits are extremely dependent on circuit parameters selection. Comparisons between MATLAB simulations and Multisim simulation results show that they are consistent with each other and demonstrate that changing attractors of the chemical oscillating chaotic system exist. It is conformed that circuit parameters selection can be effective to control and realize chaotic circuits. Originality/value The different attractors of the novel chemical oscillating chaotic system are investigated by changing the initial values under fixed parameters. The characteristic of the chemical oscillating attractor is that the basin of attraction of the three-dimensional attractor is located in the first quadrant of the eight quadrants of the three-dimensional space, and the ranges of the three variables are positive. This is because the concentrations of the three chemical substances are all positive.

LQR/LQG attitude stabilization of an agile microsatellite with CMG

2017 ◽  
Vol 89 (2) ◽  
pp. 290-296 ◽  
Author(s):  
Javad Tayebi ◽  
Amir Ali Nikkhah ◽  
Jafar Roshanian
Keyword(s):  
Attitude Control ◽  
Control Strategies ◽  
Linear Quadratic Regulator ◽  
Stabilization System ◽  
Linear Quadratic ◽  
Content Type ◽  
Attitude Stabilization ◽  
Control Moment ◽  
Angular Velocities ◽  
Simulation Results

Purpose The purpose of the paper is to design a new attitude stabilization system for a microsatellite based on single gimbal control moment gyro (SGCMG) in which the gimbal rates are selected as controller parameters. Design/methodology/approach In the stability mode, linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) control strategies are presented with the gimbal rates as a controller parameters. Instead of developing a control torque to solve the attitude problem, the attitude controller is developed in terms of the control moment gyroscope gimbal angular velocities. Attitude control torques are generated by means of a four SGCMG pyramid cluster. Findings Numerical simulation results are provided to show the efficiency of the proposed controllers. Simulation results show that this method could stabilize satellite from initial condition with large angles and with more accuracy in comparison with feedback quaternion and proportional-integral-derivative controllers. These results show the effect of filtering the noisy signal in the LQG controller. LQG in comparison to LQR is more realistic. Practical implications The LQR method is more appropriate for the systems that have project models reasonably exact and ideal sensors/actuators. LQG is more realistic, and it can be used when not all of the states are available or when the system presents noises. LQR/LQG controller can be used in the stabilization mode of satellite attitude control. Originality/value The originality of this paper is designing a new attitude stabilization system for an agile microsatellite using LQR and LQG controllers.

Sign in / Sign up

Export Citation Format

Share Document