Attitude Controller Design Research Articles

Attitude Control Design and Simulation Analysis of Quadrotor Based on Active Disturbance Rejection Control

In this paper, the attitude control problem based on active disturbance rejection control (ADRC) is studied for nonlinear underactuated quadrotor aircraft with parametric uncertainties and modeling disturbances. The simplified dynamics model of the quadrotor is established by using Newton-Euler equation, and the ADRC is applied to control the attitude control of the quadrotor. Finally, through numerical simulations, the performance of the ADRC and traditional PID algorithm are compared, the results show that the attitude control algorithm based on ADRC has better performance, and has excellent ability to resist disturbance.

Uncertainties and Design of Active Aerodynamic Attitude Control in Very Low Earth Orbit

This paper discusses the design and the performance achievable with active aerodynamic attitude control in very low Earth orbit, i.e., below 450 km in altitude. A novel real-time algorithm is proposed for selecting the angles of deflection of aerodynamic actuators providing the closest match to the control signal computed by a selected control law. The algorithm is based on a panel method for the computation of the aerodynamic coefficients and relies on approximate environmental parameters estimation and worst-case scenario assumptions for the re-emission properties of space materials. Discussion of results is performed by assuming two representative pointing maneuvers, for which momentum wheels and aerodynamic actuators are used synergistically. A quaternion feedback proportional-integral-derivative (PID) controller implemented in discrete time is assumed to determine the control signal at a sampling frequency of 1 Hz. The outcome of a Monte Carlo analysis, performed for a wide range of orbital conditions, shows that the target attitude is successfully achieved for the vast majority of the cases, thus proving the robustness of the approach in the presence of environmental uncertainties and realistic attitude hardware limitations.

Data-Driven Backstepping Sliding-Mode Control of Disturbed QUAVs

Suffering from consistent external disturbances and unavailable kinetic dynamics, a data-driven backstepping sliding-mode control (DBSMC) scheme by the combination of backstepping technique and data-driven sliding-mode control is innovatively proposed for complex quadrotor unmanned aerial vehicles (QUAVs). To maintain the salient advantages of traditional PID algorithm, a data-driven PD-type sliding-mode surface is first designed for attitude subsystem, and thereby contributing to an efficient PD control law while with strong robustness and model-independent property. Then, the virtual control strategy and backstepping technique are further incorporated into the position controller design. In light of the virtual control philosophy, the proposed attitude controller and position controller are efficiently cohered in a cascade form, and the closed-loop stability pertaining to the DBSMC scheme can be ensured theoretically. Eventually, the effectiveness of the devised DBSMC scheme is evaluated via simulation studies.

Robust Control Design for Accurate Trajectory Tracking of Multi-Degree-of-Freedom Robot Manipulator in Virtual Simulator

Robot manipulators have complex dynamics and are affected by significant uncertainties and external disturbances (perturbations). Consequently, determining the exact mathematical model of a robot manipulator is a tedious task. Accordingly, accurate trajectory tracking is a dominant feature in the design of position control for robot manipulators. The main objective of this research is to design a robust and accurate position control for a robot manipulator despite the absence of an exact model. For this purpose, an extended state observer (ESO)-based sliding mode control (SMC) is proposed. The main concept in the ESO is to define and estimate the assumed perturbation, which includes known and unknown system dynamics, uncertainties, and external disturbances. Additionally, the ESO estimates the system states. This estimated perturbation information, which is combined with the SMC input, is utilized as a feedback term to compensate for the effect of the actual perturbation. The perturbation compensation improves the controller performance, resulting in a slight position error, less sensitivity to perturbation, and a small switching gain required for the SMC. The advantage of the proposed algorithm is that it only requires partial state information and position feedback. Thus, identifying the system parameters for the nominal model before designing the controller is unnecessary. The proposed algorithm is implemented and compared with the conventional SMC and the SMC with a sliding perturbation observer (SMCSPO) in a virtual environment based on MATLAB SimMechanics. The comparison results validate the robustness of the proposed technique in the presence of perturbation and show that the technique has a significantly reduced trajectory tracking error than the conventional SMC and SMCSPO.

A Generalized Multivariable Adaptive Super-Twisting Control and Observation for Amphibious Robot

This paper aims at the problem of fast stability control of amphibious robot after state switch. A novel method named as generalized multivariable adaptive super-twisting algorithm (GMASTA) is proposed for the finite time attitude control of amphibious robot. In the proposed method, the standard multivariate super-twisting algorithm is improved by introducing a linear term and a higher power term, in order to reduce convergence time and chattering. In addition, the adaptive gain is employed based on a disturbance observer which can avoid a conservative overestimation of the disturbance. For the designed attitude controller, the finite time stability is proved by Lyapunov method. Two numerical examples were carried out. The results from the first example show that GMSTA is better than MSTA in convergence and robustness. The other example is used to illustrate that the disturbance observer based on the GMASTA can realize the accurate observation of the integrated interference. Compared with PID, the proposed method based on GMASTA can converge faster and has better robustness.

Performance Evaluation of Different Control Methods for an Underactuated Quadrotor Unmanned Aerial Vehicle (QUAV) with Position Estimator and Disturbance Observer

The main aim of this manuscript is to design and demonstrate the performance of different control algorithms with position estimator and disturbance observer to track the helical trajectory by an underactuated quadrotor craft under the influence of unmodelled dynamic factors and external disturbances. The manuscript consists of the derivations related to the kinematics and dynamics of quadrotor dully derived using the Newton Euler approach. It is one of the strenuous tasks to stabilize and control the quadrotor for helical trajectory tracking since it is an underactuated mechatronic system. In addition to this, with inclusion of unmodelled dynamic factors, it faces some of the serious transient and steady-state issues including Zeno noise. In this research manuscript, dual-loop single-dimension fuzzy sliding mode control (DLSDF-SMC) is proposed to improve the helical trajectory tracking performance, and to tackle the unmodelled dynamic factors, a state feedback controller is proposed consisting of a position estimator and disturbance observer design. The entire system is distributed into two subsystems such that within the angular subsystem, the attitude control is proposed using DLSDF-SMC, and for the translational subsystem, the paper proposes the position control design based on the hyperbolic function to avoid the gimbal lock issue. The overall stability of the proposed closed-loop control scheme is also proved. The simulation work for the proposed algorithm is performed using MATLAB and Simulink software and compared with the conventional sliding mode control (SMC) and fuzzy-based SMC control designs. This work demonstrates that the DLSDF-SMC control technique with position estimator and disturbance observer design in feedback not only improves the aggressive maneuvers while tracking the helical trajectory but also tackles the transient and steady-state issues.

ESO-based nonlinear flying boom attitude control with the handling qualities requirement

Attitude control is an important component of the flying boom system and plays a key role in air-to-air refuelling. A flying boom attitude control task is usually constituted by two subtasks. The first is to reject disturbances in the flight environment, and the second is to enhance handling qualities so that the flying boom can be efficiently and safely navigated into the refuelling receptacle by the boom operator. This paper presents a novel extended state observer (ESO)-based nonlinear flying boom attitude controller design method. To solve the first subtask, the ESO is introduced to estimate the disturbances and uncertainties of the flying boom. Based on the estimation, a nonlinear feedback controller is designed to reject the disturbances in real time. With the support of Lyapunov stability criteria, it is proved that the desired attitude trajectories can be bounded tracked by the flying boom under the proposed controller and the closed-loop dynamics of the system converge to a second-order reference model. To solve the second subtask, the parameters of the reference model are selected with desired handling qualities based on a handling qualities criterion of the flying boom. With the proposed controller, the flying boom system can have both high tracking performance and desired handling qualities. Comparisons among the proposed method and the related methods are simulated to reveal that the proposed method performs better in terms of tracking performance and robustness. Besides, a series of experiments are made on a simulator to validate that the proposed controller can achieve the desired handling qualities.

Model free adaptive control design for a tilt trirotor unmanned aerial vehicle with quaternion feedback: Theory and implementation

SummaryThis article focuses on the attitude and altitude tracking control of the tilt trirotor unmanned aerial vehicle (UAV) which is subject to modeling uncertainties and unknown external disturbances. A novel model free adaptive controller is designed to achieve asymptotic tracking control of the UAV attitude and altitude channels. The control scheme is based on the data driven strategy, and relies on the input/output data to estimate the system dynamics online. Furthermore, the discrete sliding mode algorithm is combined to enhance the system robustness, and the quaternion feedback is employed to avoid the singularity associated with the attitude control design. The stability of closed‐loop system and the convergence of the tracking errors are proved. And real time flight experiments are preformed on a tilt trirotor UAV control testbed. The experimental results verify the effectiveness of the proposed control scheme and achieve a strong robustness with respect to the modeling uncertainties and unknown external disturbances.

Robust Nonlinear Position Control with Extended State Observer for Single-Rod Electro-Hydrostatic Actuator

In the existing literature, studies on position controller design using only position feedback, considering the disturbances for single-rod electro-hydrostatic actuators (EHAs), have not been reported. Herein, we propose a robust nonlinear position control with an extended state observer (ESO) for single-rod EHAs. A new EHA model that consists of position, velocity, and acceleration with an internal state variable is developed. Instead of the separated port pressure dynamics, the acceleration dynamics were defined. The external disturbance, model, and input function uncertainties were lumped into a disturbance. An ESO is developed to estimate the disturbance, as well as the position, velocity, and acceleration. In practice, it is difficult to accurately estimate the disturbance because it includes the external disturbance, system dynamics, and input function uncertainty. The poor estimation performance may degrade the position tracking performance, but a high gain cannot be used to suppress the estimation error because of the measurement noise amplification. To resolve this problem, a robust nonlinear position controller is developed via a backstepping procedure. In the controller, a nonlinear gain is implemented to sufficiently suppress position tracking without the use of a high gain. The stability of the closed-loop system is mathematically proven using the input-to-state stability. The proposed method is simple and suitable for real-time control.

Optimal PID and fuzzy logic based position controller design of an overhead crane using the Bees Algorithm

Different industrial applications frequently use overhead cranes for moving and lifting huge loads. It applies to civil construction, metallurgical production, rivers, and seaports. The primary purpose of this paper is to control the motion/position of the overhead crane using a PID controller using Genetic Algorithms (GA) and Bee Algorithms (BA) as optimization tools. Moreover, Fuzzy Logic modified PID Controller is applied to obtain better controller parameters. The mathematical model uses an analytical method, and the PID model employs Simulink in MATLAB. The paper presents the PID parameters determination with a different approach. The development of membership functions, fuzzy rules employ the Fuzzy Logic toolbox. Both inputs and outputs use triangular membership functions. The result shows that the optimized value of the PID controller with the Ziegler-Nichols approach is time-consuming and will provide only the initial parameters. However, PID parameters obtained with the optimization method using GA and BA reached the target values. The results obtained with the fuzzy logic controller (0.227% overshoot) show improvement in overshoot than the conventional PID controller (0.271% overshoot).

A Gimballed Control Moment Gyroscope Cluster Design for Spacecraft Attitude Control

This paper addresses the problem of singularity avoidance in a cluster of four Single-Gimbal Control Moment Gyroscopes (SGCMGs) in a pyramid configuration when used for the attitude control of a satellite by introducing a new gimballed control moment gyroscope (GCMG) cluster scheme. Four SGCMGs were used in a pyramid configuration, along with an additional small and simple stepper motor that was used to gimbal the full cluster around its vertical (z) axis. Contrary to the use of four variable-speed control moment gyroscopes (VSCMGs), where eight degrees of freedom are available for singularity avoidance, the proposed GCMG design uses only five degrees of freedom (DoFs), and a modified steering law was designed for the new setup. The proposed design offers the advantages of SGCMGs, such as a low weight, size, and reduced complexity, with the additional benefit of overcoming the internal elliptic singularities, which create a minor attitude error. A comparison with the four-VSCMG cluster was conducted through numerical simulations, and the results indicated that the GCMG design was considerably more efficient in terms of power while achieving a better gimbal configuration at the end of the simulation, which is essential when it is desired for different manoeuvres to be consecutively executed. Additionally, for a nano-satellite of a few kilograms, the results prove that it is feasible to manufacture the GCMG concept by using affordable and lightweight commercial off-the-shelf (COTS) stepper motors.

The Overall Optimization and Design of the Long March 5 Launch Vehicle

The overall key technical research of the Long March 5 launch vehicle is introduced, such as the optimization design of large low temperature launch vehicle aerodynamic shape, attitude control design of swing booster engine, and large strap-on launch vehicle force and thermal environment analysis method, etc. The overall optimization technology scheme is advanced. New design and simulation technology are adopted and verified through the large ground test. Long March 5 achieves the 14-ton carrying capacity of GTO, and the overall technology reaches the international advanced level of similar launch vehicles. To meet the needs of deep space exploration missions, the overall technical research level of Long March 5 has been optimized and improved.

The model of a permanent magnet DC motor in time domain and frequency domain based on Bond Graph modelling and design of position control using PID controller

During the research work, the modelling of a permanent magnetic DC (PMDC) motor was realised in time domain and frequency domain via 4 different types of model construction. To achieve this, the Bond Graph model of the motor was determined, and based on them the system equations were defined in time domain firstly and then in frequency domain by using the Laplace transform. According to the system equations in time domain, the state-space model of the motor was also realised and implemented. Based on the system equations in frequency domain, the transfer function of the position control loop was realised. As the further part of the research work, PID control-based position control was designed in both time domain and frequency domain. The controller was tuned according to the Ziegler-Nichols method. Finally, the models were compared from the point of view of behaviour during the tuning process. The models were implemented in LabVIEW environment produced by the National Instruments.

Simulation analysis of liquid sloshing separation in spacecraft with tank based on SPH method

<p indent=0mm>The separation of spacecraft in orbit is based on multibody dynamics in a space microgravity environment, while liquid sloshing is studied based on complex nonlinear dynamics. In this study, the smoothed particle hydrodynamics (SPH) method was used to simulate liquid sloshing with a free surface in a spacecraft tank, and the separation dynamic model of the spacecraft and liquid fuel was established. Through the analysis of spacecraft separation dynamics and fluid–structure coupling dynamics, the problem of the influence of sloshing of the liquid in the fuel tank on spacecraft separation attitude was solved. The interference force and torque of liquid sloshing on the spacecraft can be obtained from the model fluid–structure coupling dynamics calculation. The separation attitude of spacecraft with liquid sloshing in the tank is different from that based on a rigid body assumption. The liquid levels affect the calculation results of spacecraft separation attitude, interference force, and torque. The analysis results provide a reference for the optimization design and separation safety design of the spring separation mechanism and improve the reliability of spacecraft attitude control design.

A Quadratic Programming Based Neural Dynamic Controller and Its Application to UAVs for Time-Varying Tasks

A quadratic programming based neural dynamic (QPND) controller design method is proposed for time-varying trajectory tracking of unmanned aerial vehicles (UAVs). Different from the traditional controller frameworks which only use pitch and roll angles to achieve the horizontal movement of the UAV, all the three attitude angles, i.e., roll, pitch and yaw angles, are applied for horizontal moving in this paper. There are at least three great superiorities of the proposed QPND controller. Firstly, three attitude angles can be coordinated control since the quadratic programming framework incorporates three attitudes. Secondly, the new framework enables the UAV to achieve the additional performance criteria or to perform subtasks. Third, the new controller can track time-varying trajectories due to neural dynamic approach. Specifically, the design process of the controller is divided into position controller design, attitude controller design and quadratic programming formulation. Finally, simulation experiments verify the feasibility and high efficiency of the proposed controller and its superiority compared with some state-of-the-art UAV controllers.

Broad learning system-based adaptive optimal control design for dynamic positioning of marine vessels

Broad learning system-based adaptive optimal control design for dynamic positioning of marine vessels

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

PurposeThe 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/approachIn 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.FindingsAccording 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 implicationsThe 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/valueThis 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.

Hover flight control of X-shaped flapping wing aircraft considering wing–tail interactions

The dynamic modelling and attitude controller design of a flapping wing aircraft, Beihawk, were investigated in this study. The aircraft features of an X-shaped flapping wing configuration, tail control surfaces installed downstream of the main flapping wings for roll and pitch control, and a tail rotor for yaw control. Unsteady effects including partial leading edge suction, induced flow, and post-stall behaviour, were considered in the aerodynamic modelling. Flapping-wing-induced flow was found to be crucial to the tail control force generation for the utilized aircraft layout. A periodically time-varying wing–tail interaction model was thus established, based on which a double-loop controller was designed to enable stable hovering of the aircraft. The stability of the nonlinear hovering-based manoeuvre was studied by manifold theory, based on the proposed wing–tail interaction model. Simulations and flight experiments on Beihawk were conducted to verify the proposed theory. It was found that the controller considering wing–tail interaction effect enabled more stable hover flight compared with traditional PD controller. In addition, it was found a wider stability region can be obtained by a higher flapping-wing-induced flow velocity. The functions between this velocity and the influencing factors, such as thrust force, wing span and tail installation position, are also presented. Besides, a visual parameter stability boundary between the vertical and pitching velocity is given. Relevant conclusions are vital in active flight envelope protection.

A Nonlinear Magnetic Stabilization Control Design for an Externally Manipulated DC Motor: An Academic Low-Cost Experimental Platform

The main objective of this paper is to present a position control design to a DC-motor, where the set-point is externally supplied. The controller is conceived by using vibrational control theory and implemented by just processing the time derivative of a Hall-effect sensor signal. Vibrational control is robust against model uncertainties. Hence, for control design, a simple mathematical model of a DC-Motor is invoked. Then, this controller is realized by utilizing analog electronics via operational amplifiers. In the experimental set-up, one extreme of a flexible beam attached to the motor shaft, and with a permanent magnet fixed on the other end, is constructed. Therefore, the control action consists of externally manipulating the flexible beam rotational position by driving a moveable Hall-effect sensor that is located facing the magnet. The experimental platform results in a low-priced device and is useful for teaching control and electronic topics. Experimental results are evidenced to support the main paper contribution.

An adaptive control design for dynamic positioning of unmanned surface vessels having actuator dynamics

An adaptive control design for dynamic positioning (DP) of unmanned surface vessels is addressed in this study. The control design is realized by taking actuator dynamics into account for obtaining a DP system where distribution of generalized forces to the actuators is considered. Owing to this approach DP system is made suitable for unmanned surface vessels having actuators equal to or more than number of generalized forces. All parameters of the surface vessel's body and actuator dynamics except thrust configuration matrix are assumed to be uncertain for the proposed control design. The parametric uncertainties are coped with adaptive compensation rules while the designed controller is equipped with a term that provides the robustness of the designed controller against disturbances including internal and external unmodeled effects. Backstepping control design approach is preferred for the control design process by considering the appropriateness of this approach for the system model of unmanned surface vessels include actuator dynamics. Theoretical proof of the designed controller is realized via Lyapunov–based arguments. Simulation studies where the efficiency of the designed controller is observed for both of aforementioned cases are conducted for the performance demonstration of the designed controller.