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dynamics and control OF A GYROSCOPE-STABILIZED PLATFORM IN A SELF-PROPELLED ANTI-AIRCRAFT SYSTEM

JOURNAL OF THEORETICAL AND APPLIED MECHANICS 2010年第1期48卷 5-26页

作者： Koruba, Zbigniew Dziopa, Zbigniew Krzysztofik, Izabela Kielce Univ Technol Fac Mechatron & Machine Bldg Kielce Poland

The paper presents a mathematical model of a triaxial gyroscopic platform oil a moving platform base (motor vehicle). control software platforms are designated with the inverse dynamics of the duties, while the control correction - using the LQR method. The considered platform can be used as an independent observation base for systems, cameras, parcels or gun machines. In the present study, it is shown in its application to stabilization of anti-aircraft missile launchers.

关键词： antiaircraft system gyroscope dynamics and control gyroscope-stabilized platform

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dynamics and control of spacecraft solar array deployment considering physical contacts between locking mechanisms

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ACTA ASTRONAUTICA 2022年 195卷 481-492页

作者： Wang, Hongdong Wang, Jianyao Shanghai Jiao Tong Univ State Key Lab Ocean Engn Shanghai 200240 Peoples R China Shanghai Jiao Tong Univ Key Lab Marine Intelligent Equipment & Syst Minist Educ Shanghai 200240 Peoples R China

The numerical simulation of the deployment and locking process of flexible appendages is an important topic in the overall design of spacecraft. In the existing research, the connecting mechanism between the solar panels is usually regarded as an ideal revolute constraint, and the locking process is simulated by applying a virtual lock torque related to the deployment angle. However, this method cannot obtain the physical contact force history, and because the physical meaning of the stiffness term in the lock torque function is not clear, it is difficult to accurately illustrate the frequency characteristics of the flexural vibration of the panels in the post-lock phase. In fact, the locking process is a frequent contact-impact process between the lock pin and groove. In this study, a typical deployable spacecraft with torsion-spring-driven panels were investigated numerically. The locking mechanism is modeled as a physical entity, and the continuous contact force model between the lock pin and groove is established. The contact stiffness of cylindrical line-contact is given by preloading calculation using the finite element method. Based on the multibody dynamics, rigid body model and flexible body model of the solar panels are established respectively. Through the comparison between the numerical simulation results of the two models, it is found that the rigid body model will produce excessive contact force and false high-frequency vibration. Furthermore, the attitude PD controller of spacecraft is designed, and the difference of system dynamic response in the deployment process under the main-body free state and the main-body controlled state is studied. The vibration frequency under the main-body controlled state is close to the first-order natural frequency of the structural finite element analysis, which verifies the rationality of the calculation results of the model.

关键词： Solar array Deployment and locking Contact-impact dynamics and control Flexible panel

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dynamics and control of a periodically forced microalgae culture 12

Dynamics and control of a periodically forced microalgae cul...

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12th International-Federation-of-Automatic-control (IFAC) Symposium on dynamics and control of Process Systems including Biosystems (DYCOPS)

作者： Martinez, Carlos Mairet, Francis Martinon, Pierre Bernard, Olivier UPMC Univ Paris 06 Univ Cote dAzur INRIA INRACNRSBIOCORE Team Sophia Antipolis France LOV UPMC Sorbonne CNRS UMR 7093 Stn Zool BP 28 F-06234 Villefranche Sur Mer France Ecole Polytech INRIA Saclay CMAP F-91128 Palaiseau France IFREMER PBA Nantes France INRIA Sophia Antipolis 2004 Route Lucioles BP 93 F-06902 Sophia Antipolis France

Microalgae cultivation with wastewater is a promising way of reducing the energetic needs for wastewater treatment and the costs of biofuel production. However, the very turbid medium is not favorable for the development of microalgae. Indeed, light, the key element for photosynthesis, rapidly vanishes along depth due to absorption and scattering. Therefore it is crucial to understand the effects of the depth on turbid cultures. In this work, we study theoretically the long-term behavior of a continuous culture of microalgae exposed to a periodic source of light. By allowing periodic variations of the depth and the hydraulic retention time, we show that the microalgae population is forced to a periodic regime. Finally, we address numerically the problem of determining the optimal variations of the depth and the hydraulic retention time for maximizing the productivity of the culture in the periodic regime. (C) 2019, IFAC (International Federation of Automatic control) Hosting by Elsevier Ltd. All rights reserved.

关键词： dynamics and control Industrial biotechnology Wastewater Biomass productivity Microalgae

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dynamics and control of the GyroPTO Wave Energy Point Absorber under Sea Waves 10

Dynamics and Control of the GyroPTO Wave Energy Point Absorb...

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10th International Conference on Structural dynamics (EURODYN)

作者： Zhang, Zili Nielsen, Soren R. K. Basu, Biswajit Aarhus Univ Dept Engn DK-8000 Aarhus Denmark Aalborg Univ Dept Civil Engn DK-9000 Aalborg Denmark Trinity Coll Dublin Sch Engn Dept Civil Struct & Environm Engn Dublin 2 Ireland

The Gyroscopic Power Take-Off (GyroPTO) wave energy point absorber has the operational principle somewhat similar to the so-called gyroscopic hand wrist exerciser. Inside the float of GyroPTO, there is a mechanical system made up of a spinning flywheel with its spin axis in rolling contact to a ring. At certain conditions, the ring starts to rotate at a frequency equal to the excitation angular frequency. In this synchronized state, the generator is running at almost constant speed and the generated power becomes constant. In this paper, theoretical modeling of the GyroPTO device is carried out based on analytical rigid body dynamics, and a 3-DOF nonlinear model is established. Simulation results show that synchronization of the device is maintained under harmonic sea wave, but is lost easily under non-harmonic sea waves. To overcome this problem, a magnetic coupling mechanism is added between the spin axis and the flywheel, which also makes semi-active control of the device possible. A 4-DOF model is then established, and simulation results show the introduced magnetic coupling successfully enables synchronization of the device under non-harmonic sea waves. (c) 2017 The Authors. Published by Elsevier Ltd.

关键词： Gyroscopic power take-off wave energy convertor dynamics and control synchronization

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dynamics and control of a gyroscope-stabilized platform in a ship anti-aircraft rocket missile launcher

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Symposium on Mechatronic Systems, Mechanics and Materials

作者： Koruba, Zbigniew Kielce Univ Technol Fac Mechatron & Machine Bldg PL-25314 Kielce Poland

ISBN: (纸本)9783037856185

The paper presents the ways of stabilising and controlling a Ship Anti-Aircraft Rocket Missile Launcher (SAARML) with the use of a Three-Axis Gyroscope-stabilized platform (TAG). The analysis of the dynamics of the SAARML and TAG systems is conducted for the case of searching and tracking a manoeuvring air target in the conditions of interferences and the influence of kinematic forces from the base (ship's deck). Some research results are presented in a graphical form.

关键词： dynamics and control ship missile launcher gyroscope-stabilized platform

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dynamics and control of Tree-Type Manipulator Systems using Exponential Coordinates 14

Dynamics and Control of Tree-Type Manipulator Systems using ...

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14th IEEE International Conference on Automation Science and Engineering (IEEE CASE)

作者： Amar, Julien Kenji, Nagase Wakayama Univ Fac Syst Engn Wakayama 6408510 Japan

ISBN: (纸本)9781538635933

This paper aims to define a fast and easy means of designing tree-type architecture manipulator systems using exponential coordinates. Exponential coordinates allow for a simple definition of joint movements in a manipulator, which is well suited to the modeling of different complex architectures. Using this approach, it is possible to derive a unified framework for the manipulator and object dynamics in a closed-form manner. The key benefits of this methodology are its simplicity and flexibility. Using this newly derived form of dynamics, it becomes easy to change the manipulator structure from one design to another, which will simplify the optimization process in future system and control designs. A numerical example is demonstrated to prove the proposed method effectiveness.

关键词： Exponential coordinates tree-type manipulator dynamics and control grasping/manipulation

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On the dynamics and control of the Sun-Earth L_(2) tetrahedral formation

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Astrodynamics 2021年第4期5卷 331-346页

作者： Yijun Lian Zhuoxi Huo Yu Cheng College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China School of Automation Beijing University of Posts and TelecommunicationsBeijing 100876China

The dynamics and control of a tetrahedral spacecraft formation flying in the Sun-Earth L2 region is initiatively studied,based on the circular restricted three-body problem(CR3BP).Driven by the science goal of identifying extra-solar terrestrial planets and the requirement of imaging optics,a conceptional four-spacecraft triangular pyramid configuration has been proposed for the Multiple-spacecraft Exoplanet Aperture sYnthetic INterferometer(MEAYIN)project,China’s first mid-infrared interferometric imaging *** it looked promising from an optical perspective,the configuration has not been verified *** formation is required to be virtually“rigid”,because its mutual distances and inertial pointing direction must be maintained with very high accuracy during each *** this study,the spatial geometrical relationship between the four spacecraft was established by introducing the parameters of lengths,angles,and a reference *** first contribution is that a compact set of normalized factors and critical time indices are defined,which can provide a complete description of the drift of the shape and pointing direction of the configuration,caused by the unstable dynamical *** design variables are isolated and analyzed,and their individual impacts on the uncontrolled evolution of the formation are *** main results obtained reveal that the dimensions of the rigid configuration allow a free drift for a time period on the order of tens of hours,while the inertial pointing direction will be lost within merely tens of ***,to form a rigid configuration,the control challenge lies in the fact that control efforts are frequently required for each spacecraft in the fleet,owing to the diverging *** a second contribution,a simple and feasible control algorithm is proposed to maintain the rigidity of the formation *** results indicate that the associated energy cost is merely 0.05 m/s per obser

关键词： tetrahedron configuration Multiple-spacecraft Exoplanet Aperture sYnthetic INterferometer(MEAYIN) formation flying dynamics and control interferometry libration point orbit

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Integration of smart materials into dynamics and control of inflatable space structures

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JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES 2001年第6期12卷 423-433页

作者： Park, G Kim, MH Inman, DJ Virginia Polytech Inst & State Univ Ctr Intelligent Mat Syst & Struct Blacksburg VA 24061 USA

An experimental investigation of vibration testing and control of an inflated thin-film torus is presented. Lightweight inflatable structures are a viable alternative in aerospace structure design. These structures, however, pose special problems in testing and in controlling vibrations due to their extremely lightweight, flexible, and high-damping properties. In this study, we show that smart materials, which can be fully integrated into an inflatable space system, could be used as sensors/actuators in order to find modal parameters and to reduce vibrations. The results indicate the potential smart materials for use in the dynamics and control of inflated structures.

关键词： .torus Intelligent Material Systems inflated inflatable structures dynamics and control Space Structures Integration of Smart

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A novel single-stage isolated high power factor correction converter with low voltage stress: dynamics and control

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JOURNAL OF THE CHINESE INSTITUTE OF ENGINEERS 2011年第5期34卷 617-628页

作者： Yang, Sung-Pei Lin, Jong-Lick Chang Jung Christian Univ Dept Comp Sci & Informat Engn Tainan 711 Taiwan Kun Shan Univ Dept Elect Engn Tainan 710 Taiwan

The dc/dc part of a single-stage high power factor correction (HPFC) converter generally operates in continuous conduction mode to increase the output power. However, this results in a high voltage stress across the bulk capacitor of the converter at light loads. The negative magnetic feedback technique is widely applied to deal with this problem. Unfortunately, a dead band in the input current is usually caused by the negative magnetic feedback, which reduces the power factor. To overcome this drawback, a novel single-stage isolated HPFC converter with low voltage stress is proposed in this study. A high power factor is maintained even though the negative magnetic feedback technique is employed in the proposed converter. Output voltage regulation in response to variations in the line voltage and load resistance is also considered in this study. The dynamics of the proposed converter are investigated and a voltage controller is then designed. Finally, the performance of the proposed converter is experimentally verified.

关键词： single-stage isolated HPFC converter low voltage stress negative magnetic feedback dynamics and control

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A unified framework for dynamics and control of tree-type systems using exponential coordinates

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MECHANICAL SYSTEMS AND SIGNAL PROCESSING 2019年 131卷 446-468页

作者： Amar, Julien Nagase, Kenji Wakayama Univ Fac Syst Engn Wakayama 6408510 Japan

This paper proposes a rapid and convenient method to model and control tree-type architecture systems using exponential coordinates. Exponential coordinates have elegant rules on products and derivatives, which allows for a simple definition of joint movements;and are highly effective for modeling complex architectures. The grasping and manipulation of an object by robot manipulators is considered in order to illustrate our modeling and control process. Using the chain matrix representing the system architecture, we derive a unified framework for the manipulator and object dynamics in a closed form fashion. The key benefit of this methodology is its simplicity and flexibility. Using this newly derived form of dynamics, we can conveniently change the system configurations (add/delete joints and links, change direction of joint movements, etc.) from one design to another;this will more accurately satisfy the manipulation requirements and simplify the optimization process for future system and control designs. Simulators can be conveniently constructed by following the formulas derived in the paper. Numerical examples of an arm-hand system are conducted to illustrate the usage of the proposed formulas in modeling, control, and optimization process. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Exponential coordinates Tree-type system dynamics and control Grasping/manipulation

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