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Targets capture by distributed active swarms via bio-inspired reinforcement learning

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu Yue Li Jun Sun Shuyuan Du Xinpeng Di Yuguang Yang Bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

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Design of an Automatic Autonomous Mini Prone-cone Microsatellite Docking Mechanism

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Chinese Journal of Mechanical Engineering 2010年第3期23卷 353-360页

作者： LAI Yinan DAI Ye TIAN Hao ZHANG Dawei School of Mechanical and Power Engineering Harbin University of Science and Technology Harbin 150080 China department of astronautics andmechanics Harbin Institute of Technology Harbin 150001 China

The capability of docking, refueling, repairing, and updating microsatellites using automatic autonomous vehicles will be of significance critical value for design and operation of several space systems in the near feature. Automatic docking capability was successfully tested by many institutions such as National Space Development Agency in Japan, European Space Agency, National Aeronautics and Space Administration in USA, etc. However, there is still much more space for improvement of degree of automation during the process of docking with large deviations of the initial attitude. A novel automatic autonomous probe-cone docking mechanism used for microsatellite docking is proposed. This docking mechanism is designed according to the design indices such as miniaturization, degree of automation and automatic capture capability within large deviation of the initial attitude. On the basis of the virtual work principle, the dynamics modeling of the docking process is presented. The position of the contact point is then analyzed. Comprehensive system level simulation is conducted in the 13 kinds of typical operating conditions with the initial deviations. Capture performance is analyzed. The simulation results show that the docking mechanism can be smoothly captured within 2 s in all cases of large attitude deviation between the active and passive spacecrafts. A virtual prototype model of the docking mechanism is established through ADAMS for further verifying the correctness of the buffer parameter model and the autonomous docking capability. A laboratory platform is designed for on-the-ground experimental validation of the property of mini probe-cone docking mechanism. Repeated docking tests prove the proposed design of the mini probe-cone docking mechanism system for its high reliability, and automatic capture capability within large attitude range. The kinetic model of the docking capture process and the mechanism structure could provide some references for similar m

关键词： docking mechanism numerical simulation virtual prototype capture buffer parameter

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System dynamics of behaviour-evolutionary mix-game models

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Chinese Physics B 2010年第11期19卷 224-229页

作者：苟成玲高洁萍陈芳 Physics department Beijing University of Aeronautics and Astronautics Mathematics department Beijing University of Aeronautics and Astronautics

In real financial markets there are two kinds of traders： one is fundamentalist, and the other is a trend-follower. The mix-game model is proposed to mimic such phenomena. In a mix-game model there are two groups of agents： Group 1 plays the majority game and Group 2 plays the minority game. In this paper, we investigate such a case that some traders in real financial markets could change their investment behaviours by assigning the evolutionary abilities to agents： if the winning rates of agents are smaller than a threshold, they will join the other group; and agents will repeat such an evolution at certain time intervals. Through the simulations, we obtain the following findings：（i） the volatilities of systems increase with the increase of the number of agents in Group 1 and the times of behavioural changes of all agents; （ii） the performances of agents in both groups and the stabilities of systems become better if all agents take more time to observe their new investment behaviours; （iii） there are two-phase zones of market and non-market and two-phase zones of evolution and non-evolution; （iv） parameter configurations located within the cross areas between the zones of markets and the zones of evolution are suited for simulating the financial markets.

关键词： minority game model mix-game model behavioural evolution system dynamics

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Global frequency distributions of pulsations driven by sharp decrease of solar wind dynamic pressure

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Science China Earth Sciences 2015年第12期58卷 2211-2219页

作者： WANG ZhiQiang department of Space Science and Application College of Astronautics Nanjing University of Aeronautics and Astronautics

On 24 August 2005, an impulse of solar wind dynamic pressure(Psw) hit the magnetosphere. Using the high resolution geomagnetic field data from 15 ground stations and the data from Geotail and TC-1, we studied the geomagnetic pulsations at auroral latitudes driven by the sharp decrease of Psw at the trailing edge of the impulse. The results show that the sharp decrease of Psw can excite a global pulsation in the frequency range 4.3–11.6 m Hz. The pulsation has a reversal of polarization between two auroral latitude stations, a larger power spectral density(PSD) close to resonant latitude and increasing frequency with decreasing latitude. All these features indicate that the pulsations are associated with field line resonance(FLR). The fundamental resonant frequency(the peak frequency of PSD between 4.3 and 5.8 m Hz) is dependent on magnetic local time and is largest around magnetic local noon. This feature is due to the fact that the size of magnetospheric cavity is dependent on local time and smallest at noon. A second harmonic wave at about 10 m Hz is also observed, which is strongest in the daytime sector, and becomes heavily attenuated in the night sector. The comparison of the PSDs of the pulsations driven by sharp increase and sharp decrease of Psw shows that the frequency of pulsations is negatively proportional to the size of magnetopause. Since the FLR is excited by compressional cavity/waveguide waves, the above results indicate that the resonant frequency in the magnetospheric cavity/waveguide is controlled not only by solar wind parameters but also by magnetic local time of observation point.

关键词： solar wind-magnetosphere interactions plasma waves and instabilities magnetopause cusp boundary layers

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Large Eddy Simulation of Methane Non-premixed Flame Using the Laminar Flamelet Model

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Journal of Thermal Science 2011年第6期20卷 534-542页

作者： Mari Mitani Yuta Ito Nobuhiko Yamasaki department of Aeronautics and astronautics Kyushu University

The large eddy simulation (LES) using the steady laminar flamelet model is applied to a simple turbulent jet flame with 33.2% H2,22.1% CH4 and 44.7% N2 at the Reynolds number of 15,200 in order to validate the numerical methods and to investigate the flame *** the validation,the detailed experimental data of DLR-A flame is *** numerical results are in reasonable agreement with experimental results except mass fractions of minor *** the flow field,the break-down of the potential core,the vortex structure and the mixing intensity are well *** the combustion field,mass fractions of major species (H2O,CO2,CO) are well predicted *** species are well predicted *** the present study,the simulations conducted on the Cartesian and cylindrical grids with approximately 6.6× 10 5 nodes are compared.

关键词： Cartesian grid cylindrical grid validation calculation

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Active Control of Fan Noise

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Journal of Thermal Science 2008年第2期17卷 163-169页

作者： Nobuhiko YAMASAKI Hirotoshi TAJIMA department of Aeronautics and astronautics Kyushu University

In the wake-rotor interaction fan noise, a number of the interacting modes at the blade passing frequency （BPF） and its harmonics are generated which are prescribed by the number of stator and rotor blades etc. In the present study, the dominant mode is tried to be suppressed by the secondary sound from the loudspeaker actuators. One of the novel features of the present system is the adoption of the control board with the Field Programmable Gate Array （FP（3A） hardware and the LabVIEW software to synchronize the circumferentially installed loudspeaker actuators with the relative location of rotational blades under arbitrary fan rotational speeds. The experiments were conducted under the conditions of three rotational speeds of 2004, 3150, and 4002 [rpm]. The reduction in the sound pressure level （SPL） was observed for all three rotational speeds. The sound pressure level at the BPF was reduced approximately 13 [dB] for 2004 [rpm] case, but not so large reduction was attained for other cases probably due to the inefficiency of the loudspeaker actuators at high frequencies

关键词： Stator-Rotor Interaction Anti Noise Control (ANC) Cut-on Control

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Observer Design Based on Self-Recurrent Consequent-Part Fuzzy Wavelet Neural Network

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Tsinghua Science and Technology 2016年第5期21卷 544-551页

作者： Xin Wen Xin Li department of Aeronautics and astronautics Shenyang Aerospace University Shenyang 110136 China School astronautics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

In this paper, we propose and construct an observer design based on a Self-Recurrent Consequent-Part Fuzzy Wavelet Neural Network（SRCPFWNN） for a class of nonlinear system. We use a Self-Recurrent Wavelet Neural Network（SRWNN） to construct a self-recurrent consequent part for each rule of the Takagi-Sugeno-Kang（TSK） model in the SRCPFWNN and analyze the structure of the fuzzy wavelet neural network model. Based on the Direct Adaptive Control Theory（DACT） and a back propagation-based learning algorithm, all parameters of the consequent parts are updated online in the SRCPFWNN. On this basis, we propose a design method using an adaptive state observer based on an SRCPFWNN for nonlinear systems. Using the Lyapunov function, we then prove the stability of this observer design method. Our simulation results confirm that the observer can accurately and quickly estimate the state values of the system.

关键词： Takagi-Sugeno-Kang (TSK) fuzzy model activation functions state observer nonlinear systems simulation

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Transport properties of a random binary side-coupled chain

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Chinese Physics B 2009年第6期18卷 2498-2501页

作者：胡冬生卢秀娟张永梅朱陈平 department of Applied Physics Nanjing University of Aeronautics and Astronautics College of International Education Nanjing University of Aeronautics and Astronautics department of Applied Physics Nanjing University of Aeronautics and Astronautics

We investigate the transport properties of a random binary side-coupled chain by using the transfer-matrix technique. It is found that there are resonant states in the systems with short-range correlations between the host chain atoms and the side-coupled atoms. The analytic expressions for the extended states are also presented in the systems with the side couplings between like atoms and between unlike atoms.

关键词： localization in disordered structures extended states resonance

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Study of the theoretical tensile strength of Fe by a first-principles computational tensile test

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Chinese Physics B 2009年第5期18卷 1923-1930页

作者：刘悦林张颖洪荣杰吕广宏 department of Physics Beijing University of Aeronautics and Astronautics

This paper employs a first-principles total-energy method to investigate the theoretical tensile strengths of bcc and fcc Fe systemically. It indicates that the theoretical tensile strengths are shown to be 12.4, 32.7, 27.5 GPa for bcc Fe, and 48.1, 34.6, 51.2 GPa for fcc Fe in the [001], [110] and [111] directions, respectively. For bcc Fe, the [001] direction is shown to be the weakest direction due to the occurrence of a phase transition from ferromagnetic bcc Fe to high spin ferromagnetic fcc Fe. For fcc Fe, the [110] direction is the weakest direction due to the formation of an instable saddle-point ＇bct structure＇ in the tensile process. Furthermore, it demonstrates that a magnetic instability will occur under a tensile strain of 14%, characterized by the transition of ferromagnetic bcc Fe to paramagnetic fcc Fe. The results provide a good reference to understand the intrinsic mechanical properties of Fe as a potential structural material in the nuclear fusion Tokamak.

关键词： Fe theoretical tensile strength phase transition first-principles computational tensiletest

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Linear Unsteady Aerodynamic Forces on Vibrating Annular Cascade Blades

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Journal of Thermal Science 2003年第2期12卷 138-143页

作者： TaketoNagasaki NobuhikoYamasaki department of Aeronautics and astronautics Kyushu UniversityFukuokaJapanDepartment of Aeronautics and AstronauticsKyushu UniversityFukuokaJapan

The paper presents the formulation to compute numerically the unsteady aerodynamic forces on the vibrating annular cascade *** formulation is based on the finite volume *** applying the TVD scheme to the linear unsteady calculations,the precise calculation of the peak of unsteady aerodynamic forces at the shock wave location like the delta function singularity becomes possible without empirical *** a further feature of the present paper,results of the present numerical calculation are compared with those of the double linearization theory(DLT),which assumes small unsteady and steady disturbances but the unsteady disturbances are much smaller than the steady *** DLT requires far less computational resources than the present numerical calculation,the validation of DLT is quite important from the engineering point of *** the conditions of small steady disturbances,a good agreement between these two results is observed,so that the two codes are *** comparison also reveals the limitation on the applicability of DLT.

关键词： CFD unsteady flows cascade Euler equations TVD scheme.

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