A method of using fuzzy hypergraphs to evaluate structural and technological survivability of attitude control systems for unmanned spacecraft

2020 ◽  
pp. 103-113
Author(s):  
Aleksandr N. PAVLOV ◽  
Dmitry A. PAVLOV ◽  
Valentin N. VOROTYAGIN
Keyword(s):  
Attitude Control ◽  
Control Process ◽  
Formal Representation ◽  
Plan Implementation ◽  
Operational Conditions ◽  
Critical Elements ◽  
Unmanned Spacecraft ◽  
Fuzzy Hypergraphs ◽  
Onboard System ◽  
Original Approach

Successful completion of a mission by an unmanned spacecraft (USC), both under nominal operational conditions both under examined contingencies and unexamined off-nominal situations is possible through designing survivability into the USC onboard system (OS). An analysis of current methods for evaluating USC OS survivability during their configuration management and reconfiguration under conditions of examined in-flight contingencies widely used in the design and development of the said USC has shown that these methods are not acceptable for evaluating the USC OS survivability in case of unexamined off-nominal situations in flight. This calls for development of conceptually novel methodological and procedural framework for evaluating structural survivability of USC OS configurations that take into account the level of participation of functional elements (FE) and OS subsystems in the USC control operations under various scenarios of the mission plan implementation. The paper proposes an original approach to evaluating the structural and technological survivability of the USC OS based on a fuzzy hypergraph formal representation of the operations to control the USC attitude, where the edges of the hypergraph connect the FE and OS subsystems that support the implementation of this or that specific control process. The paper also shows how one could use for the quantitative evaluation of the structural and technological survivability of a specific USC OS configuration the results of differentiation of a fuzzy hypergraph that could be visualized as a fuzzy hypergraph of technological independence of OS FE. Such an approach makes it possible to analyze the effects of FE on OS, identify the most critical elements, which have the lowest technological independence under mission plan implementation conditions, which could be used for providing a rationale for the required level of structural and functional redundancy of USC elements and subsystems introduced during various phases in its life cycle. Keywords: unmanned spacecraft, onboard systems survivability, fuzzy hypergraph derivative.

Control of Small Unconventional UAV Based on an On-Line Adaptive ADRC System

2014 ◽  
Vol 494-495 ◽  
pp. 1206-1211 ◽  
Author(s):  
Tong Yue Gao ◽  
Dong Dong Wang ◽  
Fei Tao ◽  
Hai Lang Ge
Keyword(s):  
Control System ◽  
Attitude Control ◽  
Control Process ◽  
Time Varying ◽  
Control Methods ◽  
Research Focus ◽  
Flight Experiment ◽  
Random Disturbances ◽  
On Line ◽  
Adaptive Ability

Recently, the UAV has become the research focus at home and abroad. this paper puts forward a unconventional type: double ducted tilting Subminiature UAV system (SUAV) , and carries out the research of the control system for this SUAV. Since SUAV flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

A Real-Time Online Adaptive Controller System of SUAV

2014 ◽  
Vol 494-495 ◽  
pp. 1050-1055
Author(s):  
Tong Yue Gao ◽  
Dong Dong Wang ◽  
Fei Tao ◽  
Hai Lang Ge
Keyword(s):  
Control System ◽  
Attitude Control ◽  
Control Process ◽  
Adaptive Controller ◽  
Control Methods ◽  
Unmanned Helicopter ◽  
Helicopter Flight ◽  
Random Disturbances ◽  
On Line ◽  
Adaptive Ability

Since Small Unmanned Helicopter flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

Leveraging synergetic information resources for angular motion control of unmanned spacecraft

2021 ◽  
pp. 127-141
Author(s):  
Vladimir S. KOVTUN ◽  
Aleksandr N. PAVLOV ◽  
Boris V. SOKOLOV ◽  
Dmitry A. PAVLOV ◽  
Valentin N. VOROTYAGIN
Keyword(s):  
Motion Control ◽  
Transitive Closure ◽  
Angular Rate ◽  
Center Of Mass ◽  
Control Process ◽  
Measured Data ◽  
Binary Relations ◽  
Spacecraft Control ◽  
Rate Vector ◽  
Unmanned Spacecraft

A key condition for accomplishing a mission of an unmanned spacecraft consists in providing it with resources. Resources can be replenished through synergetic observations of processes in cases where measured data are partially or fully missing or lacking for some of the controlled objects by means of measuring parameters of the processes characterizing the operation of other controlled objects. As an example, the paper discusses provisioning of resources for the process of controlling the motion about the center of mass by means of synergetic observations in cases where no inertial instrument was available for measuring the angular rate vector in the system controlling the motion of the geostationary communications satellite Yamal-200. Specifically, the observation is based on the operation of transitive closure of the binary relation defined on the base set of processes in the onboard systems and ground assets for radio interactions with the onboard systems of the unmanned spacecraft. Key words: unmanned spacecraft, control process, measuring data, binary relations, transitive closure, provision of resources.

LEVERAGING SYNERGETIC INFORMATION RESOURCES FOR ANGULAR MOTION CONTROL OF UNMANNED SPACECRAFT

2021 ◽  
pp. 127-141
Author(s):  
Vladimir S. KOVTUN ◽  
Aleksandr N. PAVLOV ◽  
Boris V. SOKOLOV ◽  
Dmitry A. PAVLOV ◽  
Valentin N. VOROTYAGIN
Keyword(s):  
Motion Control ◽  
Transitive Closure ◽  
Angular Rate ◽  
Center Of Mass ◽  
Control Process ◽  
Measured Data ◽  
Binary Relations ◽  
Spacecraft Control ◽  
Rate Vector ◽  
Unmanned Spacecraft

A key condition for accomplishing a mission of an unmanned spacecraft consists in providing it with resources. Resources can be replenished through synergetic observations of processes in cases where measured data are partially or fully missing or lacking for some of the controlled objects by means of measuring parameters of the processes characterizing the operation of other controlled objects. As an example, the paper discusses provisioning of resources for the process of controlling the motion about the center of mass by means of synergetic observations in cases where no inertial instrument was available for measuring the angular rate vector in the system controlling the motion of the geostationary communications satellite Yamal-200. Specifically, the observation is based on the operation of transitive closure of the binary relation defined on the base set of processes in the onboard systems and ground assets for radio interactions with the onboard systems of the unmanned spacecraft. Key words: unmanned spacecraft, control process, measuring data, binary relations, transitive closure, provision of resources.

Stability Analysis of the Microsatellite Attitude Control System

2015 ◽  
Vol 798 ◽  
pp. 297-302
Author(s):  
Meirbek Moldabekov ◽  
Suleimen Yelubayev ◽  
Kuanysh Alipbayev ◽  
Anna Sukhenko ◽  
Timur Bopeyev ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Stability Analysis ◽  
Electric Motor ◽  
Attitude Control ◽  
Control Process ◽  
Control Voltage ◽  
Control Law ◽  
Attitude Control System ◽  
Technical Specifications

The problem of development of the microsatellite attitude control system on the base of reaction wheels positioned along its principal central axes of inertia is considered in this article. As difference from the classical mathematical models describing the microsatellite motion, this article includes the mathematical model of reaction wheel which is controlled by the input voltage of the electric motor. PD-controller is used as the basis for the development of the control law for microsatellite attitude. The stability analysis of the microsatellite attitude control process was carried out with the help of Lyapunov function method. This analysis allowed to prove that obtained attitude control law provides the asymptotic stability of the microsatellite rotational motion. Further, the function of control voltage for the reaction wheel’s electric motor with account of its technical specifications was obtained based on the derived mathematical model of the reaction wheel’s dynamics. The results of performed simulation showed the effectiveness of developed control. Obtained results of the study provide a base for the use of presented approach to the development of attitude control system for microsatellites with various missions.

scholarly journals A risk-based quality control approach of Clinical Trials from a GCP institution in China

2020 ◽  
Author(s):  
Weihong Li ◽  
Yanrong Wang ◽  
Ran Chen ◽  
Xinya Dai
Keyword(s):  
Risk Assessment ◽  
Quality Control ◽  
Clinical Trials ◽  
Control Process ◽  
Quality Of Data ◽  
Plan Implementation ◽  
Control Plan ◽  
Control Approach ◽  
Assessment Development ◽  
Quality Control Process

Abstract BackgroundThis paper developed and described a risk-based quality control approach of clinical trials for clinical trial sites to improve the quality control process and ensure the quality of data.Methods Based on the trial experience, well versed experts and the findings of previous literature, an integrated risk-based quality control approach is developed centered on three cornerstones: risk assessment, central data review, and triggered, adaptive on-the-spot or remote inspection.Results We have developed an innovative risk-based quality control approach for clinical trials including risk assessment, development of quality control plan, implementation of quality control activities, development and review of quality control report, undertake actions arising from quality control report, and the update of risk assessment results or quality control plan, which fuses the idea of PDCA circle and quality by design.Conclusion Our RBQC methodology can significantly improve the clinical quality control process and the monitoring-audit triggered procedure can synchronize the activities of site, sponsor and CROs to achieve all-win. It is an innovative and effective approach.

scholarly journals Design of a Control System for an Organic Flight Array Based on a Neural Network Controller

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Bokyoung Oh ◽  
Junho Jeong ◽  
Jinyoung Suk ◽  
Seungkeun Kim
Keyword(s):  
Neural Network ◽  
Control System ◽  
Flight Control ◽  
Attitude Control ◽  
Adaptive Controller ◽  
Model Inversion ◽  
Operational Conditions ◽  
Ducted Fan ◽  
Neural Network Controller ◽  
The Neural Network

This paper presents a flight control system for an organic flight array (OFA) with a new configuration consisting of multimodularized ducted-fan unmanned aerial vehicles. The OFA has a distinguished advantage of assembling or separating with respect to its missions or operational conditions because of its reconfigurable structure. Therefore, designing a controller that can be flexibly applied in each situation is necessary. First, a dynamic modeling of the OFA based on a single ducted-fan vehicle is performed. Second, the inner loop for attitude control is designed through dynamic model inversion and a PD controller. However, an adaptive control component is needed to flexibly cope with the uncertainty because the operating environment of the OFA is varied, and uncertainty exists depending on the number of modules to be assembled and disturbances. In addition, the performance of the neural network adaptive controller is verified through a numerical simulation according to two scenarios.

scholarly journals Iterative Sliding Mode and Increment Feedback Attitude Control for On-Orbit Capturing Process of Spacecraft

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
ChunWu Yin ◽  
YouJun Ding ◽  
LiJun Song ◽  
ZhaoQiang Li ◽  
Xing He
Keyword(s):  
Attitude Control ◽  
Sliding Mode ◽  
Tracking Error ◽  
Control Process ◽  
Feedback Controller ◽  
Control Input ◽  
External Disturbances ◽  
Adaptive Sliding Mode Controller ◽  
Attitude Tracking ◽  
Input Torque

According to the characteristics of spacecraft capturing noncooperative targets in orbit, an increment feedback controller based on nonlinear iterative sliding mode is presented. Firstly, the attitude tracking error equation is established, and then, an increment feedback control law based on bounded iterative sliding modes is proposed, which does not need to estimate the uncertain moment of inertia and external disturbances. For comparing, an adaptive sliding mode controller has been designed in the paper. Some numerical simulations have been given in the presence of spacecraft on-orbit capturing noncooperative target, and the simulation results show that the increment feedback controller has strong robustness to the unknown parametric variations and external disturbances and has a smaller control input torque in control process.

A FUZZY HYPERGRAPH APPROACH TO RESEARCH OF THE VALUE OF SOCIAL NETWORKS

2019 ◽  
pp. 57-62
Author(s):  
A.N. Pavlov ◽  
B.V. Sokolov
Keyword(s):  
Social Networks ◽  
Social Network ◽  
Applied Research ◽  
Mutual Influence ◽  
Fuzzy Relation ◽  
Fuzzy Graph ◽  
Formal Representation ◽  
Social Community ◽  
The Social ◽  
Original Approach

Goal. In modern conditions, applied research is required in the field of analysis such properties of social networks as «social correlation», group interaction, the existence of «leaders of influence», the value of a social network taking into account reputation, conformism, activity of its agents. Materials and methods. The article proposes an original approach based on using the operation of differentiating a fuzzy hypergraph, building its derivative, which is a fuzzy graph of social correlation and mutual influence of network agents, and the interpretation of the results obtained in relation to social networks is presented as well. Results. Using a fuzzy hypergraphic formal representation of a social network in which the edges connect individual or group network agents that make up a particular group, coalition or configuration, and its differentiation operation, a fuzzy relation of network value is constructed, and indicators of the value of agents and the network as a whole are introduced. Conclusion. This approach allows us to analyze the influence of the leaders of agents on the social community, to assess how critical their influence is, to determine the most influential agents of the social network with the greatest value in terms of informational influences.

Deep reinforcement learning-based attitude motion control for humanoid robots with stability constraints

2020 ◽  
Vol 47 (3) ◽  
pp. 335-347 ◽  
Author(s):  
Qun Shi ◽  
Wangda Ying ◽  
Lei Lv ◽  
Jiajun Xie
Keyword(s):  
Attitude Control ◽  
A Priori ◽  
Control Process ◽  
Humanoid Robots ◽  
Content Type ◽  
Training Samples ◽  
Attitude Controller ◽  
Low Efficiency ◽  
The Stability ◽  
And Control

Purpose This paper aims to present an intelligent motion attitude control algorithm, which is used to solve the poor precision problems of motion-manipulation control and the problems of motion balance of humanoid robots. Aiming at the problems of a few physical training samples and low efficiency, this paper proposes an offline pre-training of the attitude controller using the identification model as a priori knowledge of online training in the real physical environment. Design/methodology/approach The deep reinforcement learning (DRL) of continuous motion and continuous state space is applied to motion attitude control of humanoid robots and the robot motion intelligent attitude controller is constructed. Combined with the stability analysis of the training process and control process, the stability constraints of the training process and control process are established and the correctness of the constraints is demonstrated in the experiment. Findings Comparing with the proportion integration differentiation (PID) controller, PID + MPC controller and MPC + DOB controller in the humanoid robots environment transition walking experiment, the standard deviation of the tracking error of robots’ upper body pitch attitude trajectory under the control of the intelligent attitude controller is reduced by 60.37 per cent, 44.17 per cent and 26.58 per cent. Originality/value Using an intelligent motion attitude control algorithm to deal with the strong coupling nonlinear problem in biped robots walking can simplify the control process. The offline pre-training of the attitude controller using the identification model as a priori knowledge of online training in the real physical environment makes up the problems of a few physical training samples and low efficiency. The result of using the theory described in this paper shows the performance of the motion-manipulation control precision and motion balance of humanoid robots and provides some inspiration for the application of using DRL in biped robots walking attitude control.

Sign in / Sign up

Export Citation Format

Share Document