Dynamics and control of a flexible rotating clamped-free beam by SDRE strategy

2019 ◽  
Vol 91 (7) ◽  
pp. 1018-1026
Author(s):  
Vinicius Piro Barragam ◽  
Andre Fenili ◽  
Ijar Milagre da Fonseca
Keyword(s):  
Riccati Equation ◽  
Numerical Solutions ◽  
Linear Quadratic Regulator ◽  
Flexible Beam ◽  
Problem Solution ◽  
Integration Step ◽  
Linear Quadratic ◽  
Planar Case ◽  
Content Type ◽  
Practical Implications

Purpose The purpose of this paper is the dynamic analysis of the coupled rotation and vibration motion of a system containing a central rigid body to which is attached a flexible beam. Design/methodology/approach The methodology includes the Lagrange’s formulation by using the extended Hamilton’s Principle in conjunction with the assumed modes method to describe the system of equations by ordinary differential equations. The first unconstrained mode of vibration was considered as the solution for the transversal displacement. Such mode emerges as the eigenvalue problem solution associated to the dynamics of the system. The control strategy adopted is a nonlinear analogy of the linear quadratic regulator problem as the Riccati equation is solved at every integration step during the numerical solutions. This strategy is known as state-dependent Riccati equation. Findings By means of computational simulations, it was found the relation between controlled motion and inertia ratio. Research limitations/implications This work is limited to planar case and fixed hub. Practical implications Practical implications of this work realize the design of lighter yet dexterous structures. Originality/value The contribution of this paper is the position and vibration control of a flexible beam accounting for nonlinearity effects and the fact that the structure to where it is clamped has a comparable inertia.

Autopilot design for an aircraft by using Luenberger observer design

2018 ◽  
Vol 90 (5) ◽  
pp. 858-868 ◽  
Author(s):  
Muhammad Taimoor ◽  
Li Aijun ◽  
Rooh ul Amin ◽  
Hongshi Lu
Keyword(s):  
Design Methodology ◽  
Research Work ◽  
Linear Quadratic Regulator ◽  
Observer Design ◽  
Linear Quadratic ◽  
Content Type ◽  
Luenberger Observer ◽  
Level Flight ◽  
Aerial Vehicle ◽  
The Cost

Purpose The purpose of this paper is to design linear quadratic regulator (LQR) based Luenberger observer for the estimation of unknown states of aircraft. Design/methodology/approach In this paper, the LQR-based Luenberger observer is deliberated for autonomous level flight of unmanned aerial vehicle (UAV) which has been attained productively. Various modes like phugoid and roll modes are exploited for controlling the rates of UAV. The Luenberger observer is exploited for estimation of the mysterious states of the system. The rates of roll, yaw and pitch are used as an input to the observer, while the remaining states such as velocities and angles have been anticipated. The main advantage of using Luenberger observer was to reduce the cost of the system which has been achieved lucratively. The Luenberger observer proposes sturdiness at the rate of completion to conquest over the turmoil and insecurities to overcome the privileged recital. The FlightGear simulator is exploited for the endorsement of the recital of the Luenberger observer-based autopilot. The level flight has been subjugated lucratively and has been legitimated by exploiting the FlightGear simulator. The authenticated and the validated results are offered in this paper. Microsoft Visual Studio has been engaged as a medium between the MATLAB and FlightGear Simulator. Findings The suggested observer based on LQR ensures the lucrative approximation of the unknown states of the system as well as the successful level flight of the system. The Luenberger observer is used for approximation of states while LQR is used as controller. Originality/value In this research work, not only the estimation of unknown states of both longitudinal and lateral model is made but also the level flight is achieved by using those estimated states and the autopilot is validated by using the FlightGear, while in most of the research work only the estimation is made of only longitudinal or lateral model.

An automatic system for a helicopter autopilot performance evaluation

2019 ◽  
Vol 91 (6) ◽  
pp. 880-885 ◽  
Author(s):  
Antoni Kopyt ◽  
Sebastian Topczewski ◽  
Marcin Zugaj ◽  
Przemyslaw Bibik
Keyword(s):  
Performance Evaluation ◽  
Flight Control ◽  
Automatic System ◽  
Control Algorithm ◽  
Linear Quadratic Regulator ◽  
Algorithm Analysis ◽  
Evaluation Methodology ◽  
Reference Trajectory ◽  
Linear Quadratic ◽  
Content Type

Purpose The purpose of this paper is to elaborate and develop an automatic system for automatic flight control system (AFCS) performance evaluation. Consequently, the developed AFCS algorithm is implemented and tested in a virtual environment on one of the mission task elements (MTEs) described in Aeronautical Design Standard 33 (ADS-33) performance specification. Design/methodology/approach Control algorithm is based on the Linear Quadratic Regulator (LQR) which is adopted to work as a controller in this case. Developed controller allows for automatic flight of the helicopter via desired three-dimensional trajectory by calculating iteratively deviations between desired and actual helicopter position and multiplying it by gains obtained from the LQR methodology. For the AFCS algorithm validation, the objective data analysis is done based on specified task accomplishment requirements, reference trajectory and actual flight parameters. Findings In the paper, a description of an automatic flight control algorithm for small helicopter and its evaluation methodology is presented. Necessary information about helicopter dynamic model is included. The test and algorithm analysis are performed on a slalom maneuver, on which the handling qualities are calculated. Practical implications Developed automatic flight control algorithm can be adapted and used in autopilot for a small helicopter. Methodology of evaluation of an AFCS performance can be used in different applications and cases. Originality/value In the paper, an automatic flight control algorithm for small helicopter and solution for the validation of developed AFCS algorithms are presented.

Fuzzy Logic Control for an Integrated System of a Micro-Manipulator with a Single Flexible Beam

2004 ◽  
Vol 10 (5) ◽  
pp. 755-776 ◽  
Author(s):  
N. G. Chalhoub ◽  
B. A. Bazzi
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Logic Controller ◽  
Angular Displacement ◽  
Digital Simulation ◽  
Linear Quadratic Regulator ◽  
Integrated System ◽  
Flexible Beam ◽  
Linear Quadratic ◽  
End Effector ◽  
Micro Manipulator

The use of lightweight robotic manipulators in advanced assembly and manufacturing applications is hindered by the end-effector positional inaccuracies induced by the structural deformations of the arm. To address this problem, a macro- and micro-manipulator system is considered herein. Three rigid and flexible motion controllers, consisting of an integral plus state feedback controller (ISFC), linear quadratic regulator with an integral action (LQI) and a fuzzy logic controller (FLC), have been implemented in this study. The performances of these controllers are compared based on achieving zero steady-state error in the rigid body angular displacement of the beam, damping out the unwanted vibrations, rendering the end-effector insensitive to the vibrations of the arm, and avoiding excessive control torque requirements. The digital simulation results demonstrate the superiority of the FLC over the ISFC and LQI in damping out the vibrations of the beam and reducing the gripper positional inaccuracies while requiring relatively smaller control torques. Furthermore, the results clearly demonstrate the robustness of the FLC to significant variations in the payload mass.

Vehicle direct yaw moment control system based on the improved linear quadratic regulator

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xianyi Xie ◽  
Lisheng Jin ◽  
Guo Baicang ◽  
Jian Shi
Keyword(s):  
Linear Quadratic Regulator ◽  
Objective Evaluation ◽  
Linear Quadratic ◽  
Vehicle Handling ◽  
Content Type ◽  
The Road ◽  
Direct Yaw Moment Control ◽  
Yaw Moment Control ◽  
Moment Control ◽  
Yaw Moment

Purpose This study aims to propose an improved linear quadratic regulator (LQR) based on the adjusting weight coefficient, which is used to improve the performance of the vehicle direct yaw moment control (DYC) system. Design/methodology/approach After analyzing the responses of the side-slip angle and the yaw rate of the vehicle when driving under different road adhesion coefficients, the genetic algorithm and fuzzy logic theory were applied to design the parameter regulator for an improved LQR. This parameter regulator works according to the changes in the road adhesion coefficient between the tires and the road. Hardware-in-the-loop (HiL) tests with double-lane changes under low and high road surface adhesion coefficients were carried out. Findings The HiL test results demonstrate the proposed controllers’ effectiveness and reasonableness and satisfy the real-time requirement. The effectiveness of the proposed controller was also proven using the vehicle-handling stability objective evaluation method. Originality/value The objective evaluation results reveal better performance using the improved LQR DYC controller than a front wheel steering vehicle, especially in reducing driver fatigue, improving vehicle-handling stability and enhancing driving safety.

Trajectory evaluation for manipulators with motion and sensor uncertainties

2017 ◽  
Vol 44 (5) ◽  
pp. 658-670 ◽  
Author(s):  
Ruolong Qi ◽  
Weijia Zhou ◽  
Wang Tiejun
Keyword(s):  
Design Methodology ◽  
Prior Probability ◽  
Probability Distributions ◽  
Space Station ◽  
Linear Quadratic Regulator ◽  
Goal Area ◽  
Linear Quadratic ◽  
End Effector ◽  
Content Type ◽  
Entire Trajectory

Purpose Uncertainty can arise for a manipulator because its motion can deviate unpredictably from the assumed dynamical model and because sensors might provide information regarding the system state that is imperfect because of noise and imprecise measurement. This paper aims to propose a method to estimate the probable error ranges of the entire trajectory for a manipulator with motion and sensor uncertainties. The aims are to evaluate whether a manipulator can safely avoid all obstacles under uncertain conditions and to determine the probability that the end effector arrives at its goal area. Design/methodology/approach An effective, analytical method is presented to evaluate the trajectory error correctly, and a motion plan was executed using Gaussian models by considering sensor and motion uncertainties. The method used an integrated algorithm that combined a Gaussian error model with an extended Kalman filter and a linear–quadratic regulator. Iterative linearization of the nonlinear dynamics was used around every section of the trajectory to derive all of the prior probability distributions before execution. Findings Simulation and experimental results indicate that the proposed trajectory planning method based on the motion and sensor uncertainties is indeed highly convenient and efficient. Originality/value The proposed approach is applicable to manipulators with motion and sensor uncertainties. It helps determine the error distribution of the predefined trajectory. Based on the evaluation results, the most appropriate trajectory can be selected among many predefined trajectories according to the error ranges and the probability of arriving at the goal area. The method has been successfully applied to a manipulator operating on the Chinese Space Station.

Event triggered non-inverting chopper fed networked DC motor speed synchronization

2018 ◽  
Vol 37 (2) ◽  
pp. 911-929 ◽  
Author(s):  
Suhaib Masroor ◽  
Chen Peng
Keyword(s):  
Electrical Power ◽  
Single Agent ◽  
Network Connectivity ◽  
Linear Quadratic Regulator ◽  
Lyapunov Stability Theory ◽  
System Stability ◽  
Motor Speed ◽  
Linear Quadratic ◽  
Content Type ◽  
Theoretical Concepts

PurposeThis paper aims to provide a new approach to address the problem of reaching the synchronous speed in the network connected multiple motors. Design/methodology/approachPractically, all the control approaches require continuous monitoring of the system thereby consuming extra energy. The method proposed in this paper uses an event-based approach with the multi-agent system (MAS) consensus control alongside with linear quadratic regulator control, thus saving a larger amount of energy. The proposed system is developed by using non-inverting buck boost chopper to provide necessary electrical power for the direct current motor, hence creating a single agent of bigger MAS with identical dynamics. The system stability is formulated by using Lyapunov stability theory. The proposed system is simulated via MATLAB. FindingsThe acquired simulated results validate that the proposed methodology and the multi-motor system worked successfully, thereby achieving common speed, i.e. consensus. The proposed system also validates the energy-saving concept. Practical implicationsPresently, the multiple motor synchronous speed system found application in paper-making machines, textile printing machines, offset printing, etc. The proposed study will contribute greatly to the existing methodologies and overcome their deficiencies by making the system more flexible and error-free due to the presence of network connectivity. Originality/valueThe system is simulated to verify theoretical concepts.

scholarly journals A pseudospectral method for budget-constrained infinite horizon optimal control problems

2021 ◽  
Vol 71 ◽  
pp. 145-154
Author(s):  
Angie Burtchen ◽  
Valeriya Lykina ◽  
Sabine Pickenhain
Keyword(s):  
Optimal Control ◽  
Optimal Control Problems ◽  
Numerical Solutions ◽  
Infinite Horizon ◽  
Pseudospectral Method ◽  
Linear Quadratic Regulator ◽  
Approximate Solutions ◽  
Control Problems ◽  
Linear Quadratic ◽  
Weighted Functional Spaces

In this paper a generalization of the indirect pseudo-spectral method, presented in [17], for the numerical solution of budget-constrained infinite horizon optimal control problems is presented. Consideration of the problem statement in the framework of weighted functional spaces allows to arrive at a good approximation for the initial value of the adjoint variable, which is inevitable for obtaining good numerical solutions. The presented method is illustrated by applying it to the budget-constrained linear-quadratic regulator model. The quality of approximate solutions is demonstrated by an example.

Active suppression of freeplay aeroelastic vibrations of ailerons by robust control methods with incomplete measurements

2018 ◽  
Vol 90 (4) ◽  
pp. 688-698 ◽  
Author(s):  
Franciszek Dul
Keyword(s):  
Design Methodology ◽  
Linear Quadratic ◽  
Active Suppression ◽  
Content Type ◽  
Safe Level ◽  
The Impact ◽  
Lqg Controllers ◽  
Practical Implications ◽  
Aeroelastic Vibrations ◽  
Methods Of Control

Purpose The purpose of this paper is to analyze the active suppression of the nonlinear aeroelastic vibrations of ailerons caused by freeplay by robust H∞ and linear quadratic Gauss (LQG) methods of control in case of incomplete measurements of the state of the system. Design/methodology/approach The flexible wing with nonlinear aileron with freeplay is treated as a plant-controller system with H∞ and LQG controllers used to suppress the aeroelastic vibrations. The simulation approach was used for analyzing the impact of completeness of measurements on the efficiency and robustness of the controllers. Findings The analysis shows that the H∞ method can be effectively used for suppression of nonlinear aeroelastic vibrations of aileron, although its efficiency depends essentially on completeness and types of measurements. The LQG method is less effective, but it is also able to prevent aileron vibrations by reducing their amplitudes to acceptable, safe level. Research limitations/implications Only numerical analysis was carried out for the problem described; thus, the proposed solution is of theoretical value at this stage of analysis, and its application to the real suppression of aeroelastic vibrations requires further research. Practical implications The work presents a potentially useful solution to the problem of interest and results are a theoretical basis for further research. Social implications This work may lead to a hot debate on the advantages and drawbacks of the active suppression of vibrations in the aeroelasticians community. Originality/value The work raises the important questions of practical stabilizability of the nonlinear aeroelastic systems, their dependence on completeness and types of measurements and robustness of the controllers.

Sign in / Sign up

Export Citation Format

Share Document