检索结果-内蒙古大学图书馆

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

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

来源：评论

学校读者我要写书评

暂无评论

dynamics and control of electrified pressure-swing distillation for separating a maximum-boiling azeotrope featuring small-induced shift

引用

SEPARATION AND PURIFICATION TECHNOLOGY 2023年第1期312卷

作者： Yang, Daye Zhang, Quanling Zhang, Qingjun Cui, Chengtian Nanjing Tech Univ Inst Intelligent Mfg Nanjing 211816 Jiangsu Peoples R China Levima Adv Mat Res Inst Changzhou 213161 Jiangsu Peoples R China Purdue Univ Davidson Sch Chem Engn W Lafayette IN 47907 USA

Pressure-swing distillation (PSD) is a typical thermal-driven technique for separating pressure-sensitive azeo-tropes. By implementing heat pump assisted distillation (HPAD) and self-heat recuperation technology (SHRT), the process can be modified as an electrical-driven one. Previous works have verified the overwhelming steady-state economic advantages of electrified PSDs over a conventional design. However, highly integrated electrified processes could jeopardize the dynamics and controllability. In light of potential dynamic control issues, a demonstrating case of a maximum-boiling acetone/chloroform azeotrope featuring a small pressure-induced shift was studied. Severe snowball effects were observed in these complicated electrified systems. To maintain process stability under throughput and composition disturbances, several robust control structures based on decentral-ized proportional-integral feedback controllers were developed. These control structures feature temperature controllers with no composition measurement. The results indicate that there is no conflict between the steady-state advantage and dynamic controllability. Therefore, considering the great advantages in economic and environmental aspects of electrified PSD, it is encouraged to extend process electrification measures to other distillation processes.

关键词： Pressure-swing distillation Process electrification Heat pump assisted distillation Self-heat recuperation technology dynamics and control

来源：评论

学校读者我要写书评

暂无评论

dynamics and control of thermal- versus electrical-driven pressure-swing distillation to separate a minimum-boiling azeotrope

引用

SEPARATION AND PURIFICATION TECHNOLOGY 2022年 280卷 119839-119839页

作者： Cui, Chengtian Zhang, Qingjun Zhang, Xiaodong Sun, Jinsheng Chien, I-Lung Nanjing Tech Univ Inst Intelligent Mfg Nanjing 211816 Peoples R China Tianjin Univ Sch Chem Engn & Technol Tianjin 300072 Peoples R China Natl Taiwan Univ Dept Chem Engn Taipei 10617 Taiwan

The implementations of heat integration (HI, thermal-driven), vapor recompression (VRC, electrical-driven), and self-heat recuperation (SHR, electrical-driven) in pressure-swing distillation (PSD) are available for providing energy saving and CO2 emission reduction over the conventional design (CONV, thermal-driven), exemplified by a minimum-boiling tetrahydrofuran/water. Approximately a 20 % decrease in total annual cost (TAC) and over 25 % CO2 emission reduction can be reached by using these measures. However, these steady-state advantages sometimes go along with decreases in controllability, so it is necessary to investigate the dynamics and control of these highly integrated and interacting processes. Robust temperature control structures based on decentralized proportional-integral (PI) feedback controllers are developed to tackle +/- 20% disturbances in throughput and feed composition. For the thermal-driven processes, the PSD-CONV is easily controlled with the single-end control strategy. Based on that, the effective control of PSD-HI is achieved by either pressure compensation or bypass strategy. Regarding the complicated electrical-driven arrangements, the dynamic responses of PSD-VRC and PSD-SHR indicate their controllability is comparable to those of a regular sequence. These results demonstrate that there are no conflicts between the steady-state advantages and dynamic controllability for this specific separation. Meanwhile, these electrical-driven processes can be considered to extend to other minimum-boiling azeotropes owing to their economic and environmental advantages.

关键词： Pressure-swing distillation Heat integration Vapor recompression dynamics and control Hot vapor bypass strategy

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

Open source modular simulation platform for space manipulator dynamics and control 40

Open source modular simulation platform for space manipulato...

引用

40th Chinese control Conference (CCC)

作者： Wu, Chengjie Song, Jianmei She, Haoping Huang, Liangwei Beijing Inst Technol Sch Aerosp Engn Beijing 100081 Peoples R China China Acad Space Technol Qian Xuesen Lab Space Technol Beijing 100094 Peoples R China

ISBN: (纸本)9789881563804

Space manipulator is the main actuator of on-orbit service technology, and modeling accuracy, control and simulation analysis are the key to numerical experiments. The main problem of current manipulator control simulation method is that dynamic calculation and control simulation are separated, and the simulation program is not open source. Aiming at the control simulation problem of space manipulator, an open-source modular simulation model establishment and controller design platform is proposed to realize closed-loop dynamic calculation and control simulation. The platform is based on the open source multi-body dynamics calculation software MBDyn, which establishes a modular simulation model according to the task requirements to avoid complex mathematical modeling. The Xcos simulation communication interface is developed based on the open source scientific and engineering calculation software Scilab, it exchanges data with modularized controller to realize real-time joint control simulation. Taking a six-degree-of-freedom manipulator as an example, dynamics and control simulations were carried out, and the simulation results showed the effectiveness of the platform. It can be applied to a variety of multi-body dynamics control simulation schemes, open source and has good versatility.

关键词： Space manipulator open source modular simulation platform dynamics and control MBDyn Scilab

来源：评论

学校读者我要写书评

暂无评论

dynamics and control of a periodically forced microalgae culture 12

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

Open source modular simulation platform for space manipulator dynamics and control

Open source modular simulation platform for space manipulato...

引用

第40届中国控制会议

作者： Chengjie Wu Jianmei Song Haoping She Liangwei Huang School of Aerospace Engineering Beijing Institute of Technology Qian Xuesen Laboratory of Space Technology China Academy of Space Technology

关键词： Space manipulator open source modular simulation platform dynamics and control MBDyn Scilab

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

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

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

ODYSC: A responsive educational web app for dynamics and control

引用

IFAC-PapersOnLine 2018年第4期51卷 310-315页

作者： Dekemele, Kevin Chevalier, Amélie Loccufier, Mia Ghent University Department of Electrical Engineering Metals Mechanical construction and Systems Technologiepark 914 GhentB-9000 Belgium

The Online Dynamical Systems and control (ODYSC) web application has been developed for the introductory dynamics and control courses taught to engineers and business engineering of Ghent university, accessible through http://***/. Generally speaking, the advantage of web apps over conventional software is the compatibility between operating system (OS) and devices, as only a browser is required. Recently, students bring a mobile phone to lectures. While these are often used by the students themselves as a distraction, they are actually very powerful computers capable of performing simulations of dynamical systems. Because of this, ODYSC has been designed to be responsive, working equally well on both mobile phone as on a laptop or PC. While ODYSC can serve as a distance learning tool, it can also be employed during classical lectures. While the teacher explains new concepts in dynamics or control, these can immediately be made clear through simulations on the student's phone. Before, the amount of students attending these courses were a practical limitation for organizing computer labs. Even if such infrastructure exists, the software used requires the students to code in a new language, which they are often not motivated enough to do for a single lab, or the software is associated with costly or complicated licensing. ODYSC requires no special infrastructure but a device with a browser which students themselves bring anyway. ODYSC is still in full development and for now can perform open loop and closed loop simulations on LTI systems, and plot bode plots of the system. © 2018

关键词： Students Application programs Bode diagrams Cellular telephones Computer software Curricula Dynamical systems dynamics E learning Linear systems Mobile phones Online systems Teaching Telephone sets Business engineering Closed loop simulations control education Distance learning tools dynamics and control mobile responsive WEB application

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：