Ronghua Zhang, Qingwen Ma, Xinglong Zhang, Xin Xu, Daxue Liu
{"title":"A Distributed Actor-Critic Learning Approach for Affine Formation Control of Multi-Robots With Unknown Dynamics","authors":"Ronghua Zhang, Qingwen Ma, Xinglong Zhang, Xin Xu, Daxue Liu","doi":"10.1002/acs.3972","DOIUrl":"https://doi.org/10.1002/acs.3972","url":null,"abstract":"<div>\u0000 \u0000 <p>Formation maneuverability is particularly important for multi-robots (MRs), especially when the robots are operating cooperatively in complex and dynamic environments. Although various methods have been developed for affine formation, it is still a difficult problem to design an affine formation controller for MRs with unknown dynamics. In this paper, a distributed actor-critic learning approach (DACL) in a look-ahead rollout manner is proposed for the affine formation of MRs under local communication, which improves the online learning efficiency. In the proposed approach, a distributed data-driven online optimization mechanism is designed via the sparse kernel technique to solve the near-optimal affine formation control issue of MRs with unknown dynamics as well as improve control performance. The unknown dynamics of MRs are learned offline based on precollected input-output datasets, and the sparse kernel-based approach is employed to increase the feature representation capability of the samples. Then, the proposed distributed online actor-critic algorithm for each robot in the formation includes two neural networks, which are utilized to approximate the costate functions and the near-optimal policies. Moreover, the convergence analysis of the proposed approach has been conducted. Finally, numerical simulation and KKSwarm-based experiment studies are performed to verify the effectiveness of the proposed approach.</p>\u0000 </div>","PeriodicalId":50347,"journal":{"name":"International Journal of Adaptive Control and Signal Processing","volume":"39 4","pages":"803-817"},"PeriodicalIF":3.9,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143818807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaomin Liu, Mengjun Yu, Kun Feng, Gonghe Li, Linna Zhou, Haoyu Wang, Chunyu Yang
{"title":"Cross-Scale Imperfect Data-Based Composite \u0000 \u0000 \u0000 \u0000 \u0000 H\u0000 \u0000 \u0000 ∞\u0000 \u0000 \u0000 \u0000 $$ {H}_{infty } $$\u0000 Control of Nonlinear Two-Time-Scale Systems","authors":"Xiaomin Liu, Mengjun Yu, Kun Feng, Gonghe Li, Linna Zhou, Haoyu Wang, Chunyu Yang","doi":"10.1002/acs.3974","DOIUrl":"https://doi.org/10.1002/acs.3974","url":null,"abstract":"<div>\u0000 \u0000 <p>Utilizing the cross-scale imperfect data, the reinforcement learning (RL) composite <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>∞</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {H}_{infty } $$</annotation>\u0000 </semantics></math> control of nonlinear two-time-scale (TTS) systems is proposed in the presence of unknown slow dynamics. First, with the feat of singular perturbation theory (SPT), the original <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>∞</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {H}_{infty } $$</annotation>\u0000 </semantics></math> control problem is decomposed and rearranged into standard fast and slow subproblems that have no cross terms between state, control and disturbance in the performance indices. Then, since the states of decomposed fast and slow subsystems cannot be measured perfectly, the state reconstruction mechanism is proposed based on the input-state data of the original system, and cross-scale information interaction is incorporated to correct the bias induced by the time-scale decomposition. Cross-scale composite RL algorithm is proposed with the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>∞</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {H}_{infty } $$</annotation>\u0000 </semantics></math> slow and fast controllers designed in separate time scales. Next, the stability and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>∞</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {H}_{infty } $$</annotation>\u0000 </semantics></math> performance of the TTS systems under the composite controller is analyzed considering the data inaccuracy of state reconstruction. Finally, the effectiveness of the proposed method is validated in the control application to the permanent magnet synchronous motor (PMSM) system.</p>\u0000 </div>","PeriodicalId":50347,"journal":{"name":"International Journal of Adaptive Control and Signal Processing","volume":"39 4","pages":"745-760"},"PeriodicalIF":3.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143818795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}