IET Control Theory and Applications最新文献

{"title":"Fuzzy control allocation of a positionable rotor quadrotor based on log-barrier optimization and propulsion system fault toleration","authors":"Matin Davoudi Dehkordi,&nbsp;Mohammad Danesh","doi":"10.1049/cth2.12653","DOIUrl":"10.1049/cth2.12653","url":null,"abstract":"<p>Herein, a control system and a fault tolerance method for the rotor positionable quadrotor are proposed. Quadrotors that have a variable structure are made for different purposes. The rotor-positionable quadrotor studied here, is a type of drone with a variable structure that has the ability to change the position of its rotors linearly along the axis of each arm. It can be seen that this capability can improve the drone robustness against disturbances and faults in comparison with regular quadcopters. Due to the over-actuated dynamics of this type of quadrotor, the control allocation scheme based on log-barrier optimization is employed to obtain the position and speed of each rotor. In this study, it is experimentally shown that rotor positioning not only reduces power consumption but also increases roll and pitch control inputs magnitude. Furthermore, when a fault occurs as a decrease in rotor speed, a fuzzy method is proposed to position the rotors which tolerates the fault. Finally, numerical simulations and experimental tests verified that rotor positioning can bring more robustness, reduction in power consumption, and fault tolerance in some rotor faults capabilities for quadrotors.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12653","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140678829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid nonlinear ripple-free sampled-data robust regulation with application to UAVs","authors":"Ulises Larios-Navarro,&nbsp;Horacio García-Vázquez,&nbsp;Bernardino Castillo-Toledo,&nbsp;Stefano Di Gennaro","doi":"10.1049/cth2.12649","DOIUrl":"10.1049/cth2.12649","url":null,"abstract":"<p>This paper proposes a novel solution to the problem of robust ripple-free hybrid robust regulator ensuring the elimination of intersample ripples. The paper considers a structurally stable regulation approach in the hybrid framework. A regulator is designed using this technique under periodic sampling and is applied to the nonlinear model of a quadrotor. The control of unmanned autonomous vehicles has become a research topic that is important by itself, particularly in the case of multi-rotor systems due to their versatility in various applications. Tracking a reference signal for such vehicles can be challenging, particularly when the frequency of communication is limited, or the control station is located far away. The proposed controller is hence tested for this challenging application.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12649","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140694433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An analytical adaptive optimal control approach without solving HJB equation for nonlinear systems with input constraints","authors":"Zahra Tavanaei Sereshki,&nbsp;Heidar Ali Talebi,&nbsp;Farzaneh Abdollahi","doi":"10.1049/cth2.12663","DOIUrl":"10.1049/cth2.12663","url":null,"abstract":"<p>This paper presents an analytical method to solve the optimal control problem for affine nonlinear systems with unknown drift dynamics. A new non-quadratic cost function over an infinite horizon is presented that considers input constraints and includes the cost of the feed-forward component of the control law. The mean value theorem for vector-valued functions has been used to derive an integral form of this theorem. Based on this theorem, a rigorous proof is provided demonstrating that the cost function can be converted into another form. In the presence of input constraints, this converted form enables extracting the optimal control solution without solving the HJB equation. Additionally, unknown nonlinearity effects in drift dynamics are compensated in the control input. This is accomplished by estimating the unknown drift dynamics via an adaptive neural network (NN) approach. It is proven that the states and weights of NN are uniformly ultimately bounded based on a Lyapunov technique. The necessary and sufficient conditions are provided that ensure the optimality of the infinite horizon optimal control problem with a discount factor. As a result, it is demonstrated that the proposed approach satisfies the optimality criteria. To evaluate the effectiveness of the proposed approach, simulation examples are provided.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12663","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140693525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear control of coaxial double rotor magnetic gear based on high gain observer in wind turbine","authors":"Hamideh Habibi,&nbsp;Amanj Aminnzhad,&nbsp;Mohammad Javad Khosrowjerdi","doi":"10.1049/cth2.12666","DOIUrl":"10.1049/cth2.12666","url":null,"abstract":"<p>This paper proposes a nonlinear control law with a dynamic controller based on high gain observer (HGO) for a co-axial double rotor magnetic gear (CADRMG) based on Halbach array used in wind turbines. The generalized canonical form (GCF) is used to normalize the nonlinear augmented system to achieve the dynamic control signal with a chain of integrator of system output. In addition, a tracking problem is defined to track high speed rotor (HSR) with respect to GCF. On the other hand, the HGO is used to estimate the error tracking at the expense of nonlinear terms. Furthermore, the nonlinear system observability of the augmented system is evaluated. A dynamic control law is used to solve the tracking problem based on HGO. This controller can eliminate the effect of load torque as a constant and unknown disturbance in the closed-loop system. Moreover, the closed-loop stability of the system under dynamic signal control is guaranteed. The system states estimation is calculated by recursive equations from tracking error estimations. Finally, numerical simulations are given to illustrate the theoretical results of proposed system.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12666","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140700948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of shape memory alloy actuator dynamics to design reduced-order position controller with input saturation","authors":"Mohammad Mohammadi Shahir,&nbsp;Mehdi Mirzaei,&nbsp;Maryam Farbodi,&nbsp;Sadra Rafatnia","doi":"10.1049/cth2.12665","DOIUrl":"https://doi.org/10.1049/cth2.12665","url":null,"abstract":"<p>This study focuses on the precise model estimation for a position control problem actuated by a shape memory alloy (SMA) wire. Because the hysteresis characteristic of SMA introduces complexities in system modelling and adds degrees of freedom, a model with reduced order is implemented for controller design. This model is online updated by calculating a complementary term from the measured data to compensate for the SMA actuator dynamics and other parametric uncertainties. The position controller, derived from the formulated reduced-order model, adapts itself to real conditions and is cost-effective due to the use of only displacement sensor. The saturation of the control input is modelled within the structure of a constrained optimization problem solved by Karush–Kuhn–Tucker theorem. The boundedness of mean and covariance of tracking error and its derivative is demonstrated by stochastic analysis. The experimental results conducted on a platform incorporating a SMA wire show the efficiency of the proposed system in precisely controlling the position by admissible voltage range. The comparative results with a sliding mode controller indicate higher accuracy for the proposed controller to reduce the effect of uncertainties.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12665","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141556725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast quadratic model predictive control based on sensitivity analysis and Wolfe method","authors":"Hamid Kalantari,&nbsp;Mohsen Mojiri,&nbsp;Javad Askari,&nbsp;Najmeh Zamani","doi":"10.1049/cth2.12642","DOIUrl":"10.1049/cth2.12642","url":null,"abstract":"<p>This paper proposes a new algorithm based on sensitivity analysis and the Wolfe method to solve a sequence of parametric quadratic programming (QP) problems such as those that arise in quadratic model predictive control (QMPC). The Wolfe method, based on Karush–Kuhn–Tucker conditions, has been used to convert parametric QP problems to parametric linear programming (LP) problems, and then the sensitivity analysis is applied to solve the sequence of the parametric LP problems. This strategy obtains sensitivity analysis-based QMPC (SA-QMPC) algorithm. It is proved that the computational complexity of SA-QMPC is <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>O</mi>\u0000 <mo>(</mo>\u0000 <mi>N</mi>\u0000 <msup>\u0000 <mi>n</mi>\u0000 <mn>2</mn>\u0000 </msup>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$O(Nn^2)$</annotation>\u0000 </semantics></math> for a region of the initial conditions and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>O</mi>\u0000 <mo>(</mo>\u0000 <msup>\u0000 <mi>N</mi>\u0000 <mn>2</mn>\u0000 </msup>\u0000 <msup>\u0000 <mi>n</mi>\u0000 <mn>2</mn>\u0000 </msup>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$O(N^2n^2)$</annotation>\u0000 </semantics></math> for sufficiently small sampling time and all initial conditions, where <span></span><math>\u0000 <semantics>\u0000 <mi>N</mi>\u0000 <annotation>$N$</annotation>\u0000 </semantics></math> and <span></span><math>\u0000 <semantics>\u0000 <mi>n</mi>\u0000 <annotation>$n$</annotation>\u0000 </semantics></math> are the horizon time and dimension of the state vector, respectively. Numerical results indicate the potential and properties of the proposed algorithm.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12642","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140707136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A bit rate condition for feedback stabilization of uncertain switched systems with external disturbances based on event triggering","authors":"Rui Chen,&nbsp;Qiang Ling,&nbsp;Jie Fang,&nbsp;Xihong Fei,&nbsp;Duansong Wang","doi":"10.1049/cth2.12647","DOIUrl":"10.1049/cth2.12647","url":null,"abstract":"<p>This paper studies the input-to-state stability of an uncertain switched linear system with external disturbances, whose feedback loop is closed over a digital communication network. In the network, only a finite bit rate can be provided to transmit the feedback signal and unknown network delay always exists. By using reachable set approximation and propagation methods, it can well handle with the effects of model uncertainty, external disturbances and network delay on the stability of the system. To save network resources, event-triggered sampling is taken here. Under the event-triggered sampling strategies, a new encoder is proposed, which consumes less feedback bits than the conventional time-triggered encoders. It is proven that even in the existence of model uncertainty, external disturbances and network delay, the proposed event-triggered sampling strategies require a lower feedback bit rate to stabilize the switched system than conventional periodic sampling methods.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12647","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140711331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Policy iteration for H∞ control of polynomial time-varying systems","authors":"Sajjad Pakkhesal,&nbsp;Saeed Shamaghdari","doi":"10.1049/cth2.12661","DOIUrl":"10.1049/cth2.12661","url":null,"abstract":"<p>This paper studies the <i>H_∞</i> control problem for polynomial time-varying systems. The <i>H_∞</i> control problem has been much less investigated for time-varying systems in comparison to the time-invariant systems. Approximate dynamic programming (ADP) is an optimal method to solve the control problems. Therefore, it is valuable to solve the polynomial time-varying <i>H_∞</i> control problem with the ADP approach. Considering the time as an independent variable for sum-of-squares (SOS) optimization problems, an SOS-based ADP method is proposed to solve this problem. A policy iteration algorithm is presented, where in its policy evaluation step it is sufficient to solve an optimization problem. Some constraints are added to this optimization problem to guarantee the closed-loop exponential stability. The convergence and stability properties of the proposed algorithm are stated and proven. Moreover, in order to design an <i>H_∞</i> controller with a smaller disturbance attenuation coefficient, a two-loop algorithm is suggested. Finally, the effectiveness of the proposed method is demonstrated by simulation examples.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12661","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140708988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iterative-recursive estimation of parameters of regression models with resistance to outliers on practical examples","authors":"Janusz Kozłowski,&nbsp;Zdzisław Kowalczuk","doi":"10.1049/cth2.12628","DOIUrl":"10.1049/cth2.12628","url":null,"abstract":"<p>Here, identification of processes and systems in the sense of the least sum of absolute values is taken into consideration. The respective absolute value estimators are recognised as exceptionally insensitive to large measurement faults or other defects in the processed data, whereas the classical least squares procedure appears to be completely impractical for processing the data contaminated with such parasitic distortions. Since the absolute value quality index cannot be minimised analytically, an iterative solution is used to find optimal estimates of the parameters of the underlying regression model. In addition, an approximate recursive estimator is proposed and implemented for on-line evaluation of system parameters. The convergence (basic property) of the iterative estimator is show to be proven and some aspects related to the absolute value criterion are explained. This allows for the formulation of practical conclusions and indication of directions for further research. In addition, the effectiveness of the described iterative-recursive estimation procedures is practically verified by appropriate numerical experiments.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12628","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140711265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Partial information target defense game in the presence of a line segment obstacle","authors":"Jingwen Xu,&nbsp;Qiyong He,&nbsp;Min Meng,&nbsp;Xiuxian Li,&nbsp;Jiaqi Yan","doi":"10.1049/cth2.12664","DOIUrl":"10.1049/cth2.12664","url":null,"abstract":"<p>A two-player planar target defense game where the intruder attempts to breach the circular region guarded by the defender in the presence of a fixed line segment obstacle is addressed. Based on prior research, the entire game was divided into three phases to address the partial information problem. Additionally, the impact of obstacles on the game outcome is thoroughly analyzed. In contrast to the scenario without obstacles, this paper presents redesigned strategies for both defender and intruder, accompanied by quantitative results illustrating the influence on the winning probability. Finally, illustrative examples are given to demonstrate the effect of the obstacle.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12664","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140709971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}