Liangyin Zhang, Michael Z. Q. Chen, Zhiwei Gao, Lifeng Ma
{"title":"On the explicit Hermitian solutions of the continuous-time algebraic Riccati matrix equation for controllable systems","authors":"Liangyin Zhang, Michael Z. Q. Chen, Zhiwei Gao, Lifeng Ma","doi":"10.1049/cth2.12618","DOIUrl":"10.1049/cth2.12618","url":null,"abstract":"<p>This paper proposes explicit solutions for the algebraic Riccati matrix equation. For single-input systems in controllable canonical form, the explicit Hermitian solutions of the non-homogeneous Riccati equation are obtained using the entries of the system matrix, the closed-loop system matrix, and the weighting matrix. The unknown entries of the closed-loop system matrix are solved by scalar quadratic equations. For a homogeneous Riccati equation with a zero weighting matrix, the explicit solutions are proposed analytically in terms of the system eigenvalues. The advantages of the explicit solutions are threefold: first, if the system is controllable, the solution is directly given and the invariant subspaces of the Hamiltonian matrix are not required; second, if the system is near singularity, the explicit solution has higher numerical precision compared with the solution computed by numerical algorithms; third, for a real system in the controllable canonical form, the non-negativity can be analysed for the explicit almost stabilizing solution.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12618","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139443146","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 adaptive neural design for planar rigid formation of three coleaders in unknown flowfields","authors":"Weibin Chen, Peng Xu, Yang-Yang Chen","doi":"10.1049/cth2.12617","DOIUrl":"10.1049/cth2.12617","url":null,"abstract":"<p>This article deals with the robust planar rigid formation control problem of three second-order coleaders with unknown flowfields acting on the velocity and acceleration respectively. To yield the uniform boundedness property of the resulting system, an adaptive projection is introduced to design the novel adaptive neural control law. To avoid the derivatives of Gaussian functions of neural networks, dynamic surface is used. Simulation results are provided to illustrate the effectiveness of the proposed control law.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12617","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448129","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":"Small-gain based stabilizing control for hybrid systems: Application to bipedal walking robot","authors":"Fatemeh Khademian, Mehdi Rahmani","doi":"10.1049/cth2.12612","DOIUrl":"10.1049/cth2.12612","url":null,"abstract":"<p>This study presents a systematic methodology for developing a stabilizing controller for a general hybrid systems model. The approach is based on utilizing the small-gain theorem as a means of constructing the Lyapunov function and analyzing the input–output stability of the subsystems in the feedback loop. By considering the control system in a closed-loop configuration with the hybrid system, the small-gain theorem can be applied. In this scheme, a dynamic control system is proposed that satisfies the closed-loop stability conditions. This method applies to various hybrid systems' applications due to its generality. To demonstrate the effectiveness and performance of the proposed control approach, two simulation examples, including a linear hybrid system and a bipedal walking robot, are examined.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12612","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385851","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}
Reza Ebrahimpour Derakhshan, Mohammad Danesh, Hassan Moosavi
{"title":"Disturbance observer-based model predictive control of a coaxial octorotor with variable centre of gravity","authors":"Reza Ebrahimpour Derakhshan, Mohammad Danesh, Hassan Moosavi","doi":"10.1049/cth2.12611","DOIUrl":"10.1049/cth2.12611","url":null,"abstract":"<p>This paper presents a model predictive control (MPC) approach based on the extended disturbance observer (EDOB) for trajectory tracking of a coaxial octorotor unmanned aerial vehicle (UAV). First, the system dynamic model is derived using Newton–Euler relations in the presence of time-varying centre of gravity (COG); then, a two-loop cascade structure is presented to perform the trajectory tracking task. Both loops are controlled using MPC with feedforward compensation based on the EDOB to improve disturbance rejection abilities. When the mass changes, the moment of inertia and COG are affected. The EDOB simultaneously estimates the effects of time-varying mass, external disturbances, and parametric uncertainties in six degrees of freedom. After obtaining virtual control inputs using designed controllers, constrained control allocation is used to obtain rotors speed in a valid range. The proposed control scheme is evaluated using simulation. The simulation results show the ability of the developed control strategy in accurate trajectory tracking and stable flight in different conditions and being robust to uncertainty and disturbance.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12611","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388975","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 efficient model-free adaptive optimal control of continuous-time nonlinear non-zero-sum games based on integral reinforcement learning with exploration","authors":"Lei Guo, Wenbo Xiong, Yuan Song, Dongming Gan","doi":"10.1049/cth2.12610","DOIUrl":"10.1049/cth2.12610","url":null,"abstract":"<p>To reduce the learning time and space occupation, this study presents a novel model-free algorithm for obtaining the Nash equilibrium solution of continuous-time nonlinear non-zero-sum games. Based on the integral reinforcement learning method, a new integral HJ equation that can quickly and cooperatively determine the Nash equilibrium strategies of all players is proposed. By leveraging the neural network approximation and gradient descent method, simultaneous continuous-time adaptive tuning laws are provided for both critic and actor neural network weights. These laws facilitate the estimation of the optimal value function and optimal policy without requiring knowledge or identification of the system's dynamics. The closed-loop system stability and convergence of weights are guaranteed through the Lyapunov analysis. Additionally, the algorithm is enhanced to reduce the number of auxiliary NNs used in the critic. The simulation results for a two-player non-zero-sum game validate the effectiveness of the proposed algorithm.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2023-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12610","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139160922","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":"Output controllability of impulsive Boolean control networks based on hybrid-index model","authors":"Qianya Liang, Rongpei Zhou, Jie Chen, Yong Ding","doi":"10.1049/cth2.12609","DOIUrl":"10.1049/cth2.12609","url":null,"abstract":"<p>In biological systems, impulses are often used to model mutations in gene expression. In order to describe the instantaneity of the impulse, this paper employs a hybrid-index model of impulsive Boolean networks with state-triggered impulses. Based on this model, the time-domain output controllability is investigated. Using the quotient mapping method, the hybrid-domain solutions of this model are mapped to the time-domain solutions, mathematically. Then a necessary and sufficient condition for output controllability in the time domain is presented. Finally, an example is given to demonstrate the correctness and effectiveness of the obtained results.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12609","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139171268","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":"Adaptive neural network \u0000 \u0000 \u0000 H\u0000 ∞\u0000 \u0000 $H_infty$\u0000 control for offshore platform with input delay and nonlinearity","authors":"Yun Zhang, Hui Ma, Shu-Qing Wang, Jianliang Xu, Hao Su, Jing Zhang","doi":"10.1049/cth2.12575","DOIUrl":"10.1049/cth2.12575","url":null,"abstract":"<p>In this work, an adaptive learning robust controller is proposed to suppress the vibration of offshore platforms, which are subject to waves, winds, varying control delays and parametric perturbations. To realize nonlinear uncertainty approximation under the bounded <math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>H</mi>\u0000 <mi>∞</mi>\u0000 </msub>\u0000 <annotation>$H_infty$</annotation>\u0000 </semantics></math> performance, the <math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>H</mi>\u0000 <mi>∞</mi>\u0000 </msub>\u0000 <annotation>$H_infty$</annotation>\u0000 </semantics></math> controller incorporates both an online adaptive part and an offline fixed part. The adaptive part constructed by neural networks adjusts online, while the fixed part is obtained by regulating the <math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>H</mi>\u0000 <mi>∞</mi>\u0000 </msub>\u0000 <annotation>$H_infty$</annotation>\u0000 </semantics></math> performance. Importantly, adaptive updating strategy does not require accurate values or upper bounds for real-time control delay or uncertainty. Several comparable experiments demonstrate the feasibility and effectiveness in vibration-suppression of the designed adaptive controller in shallow/deep water. This scheme significantly reduces system response variations due to structural and hydrodynamic uncertainty, as well as additional random environmental forces caused by winds.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.12575","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139184123","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}