Set the Target (Subsystem Level)

2019 ◽  
pp. 70-85
Keyword(s):  
Subsystem Level

Large-Scale Discrete-Time Interconnected Dynamical Systems

2011 ◽  
Author(s):  
Wassim M. Haddad ◽  
Sergey G. Nersesov
Keyword(s):  
Dynamical Systems ◽  
Discrete Time ◽  
Large Scale ◽  
Discrete Energy ◽  
Flow Balance ◽  
Subsystem Level ◽  
Coupling Strengths ◽  
Definition Of ◽  
Energy Dissipated ◽  
Discrete Time Dynamical Systems

This chapter develops vector dissipativity notions for large-scale nonlinear discrete-time dynamical systems. In particular, it introduces a generalized definition of dissipativity for large-scale nonlinear discrete-time dynamical systems in terms of a vector dissipation inequality involving a vector supply rate, a vector storage function, and a nonnegative, semistable dissipation matrix. On the subsystem level, the proposed approach provides a discrete energy flow balance in terms of the stored subsystem energy, the supplied subsystem energy, the subsystem energy gained from all other subsystems independent of the subsystem coupling strengths, and the subsystem energy dissipated. The chapter also develops extended Kalman–Yakubovich–Popov conditions, in terms of the local subsystem dynamics and the interconnection constraints, for characterizing vector dissipativeness via vector storage functions for large-scale discrete-time dynamical systems.

Systemic emergence under transitional uncertainty

Kybernetes ◽  
2017 ◽  
Vol 46 (9) ◽  
pp. 1527-1541 ◽  
Author(s):  
Sanwar Azam Sunny
Keyword(s):  
Scenario Planning ◽  
Low Carbon ◽  
Topic Area ◽  
Content Type ◽  
Subsystem Level ◽  
Production And Consumption ◽  
National Model ◽  
Multiple Levels ◽  
Changes Over Time ◽  
Transition Approach

Purpose The purpose of the paper is to set out ideas regarding the use of both first- and second-order cybernetics in reducing global energy-based emissions through energy technology innovation at multiple levels and to discuss necessary production and consumption patterns to facilitate such changes over time. Design/methodology/approach The paper uses a conceptual framework to estimate a national model of energy consumption and production, conceived as embedded hypercubes for different actor levels. The author has developed a model that elaborates on a multi-level ecosystem for low-carbon technology adoption and innovation, embedded within a sustainability transition framework. Findings The paper reviews product–process relationships at multiple levels and grounds the framework in a transition approach. With more contextually conceptualized framework grounded in theory, this research aims to inform future development in the topic area, given the embryonic emergence of advanced cybernetic technologies, by viewing such capabilities at the subsystem level as a unit of analysis. Originality/value The paper will be of interest to firm managers, ecologists and policymakers with a particular interest in system sciences. The framework can be applied for facilitating discussions or for scenario planning.

Constraint Wrench Formulation for Closed-Loop Systems Using Two-Level Recursions

2007 ◽  
Vol 129 (12) ◽  
pp. 1234-1242 ◽  
Author(s):  
Himanshu Chaudhary ◽  
Subir Kumar Saha
Keyword(s):  
Lagrange Multipliers ◽  
Spanning Tree ◽  
Closed Loop ◽  
Equations Of Motion ◽  
Constraint Forces ◽  
Minimal Set ◽  
Closed Loops ◽  
Closed Loop Systems ◽  
Subsystem Level ◽  
Body Level

In order to compute the constraint moments and forces, together referred here as wrenches, in closed-loop mechanical systems, it is necessary to formulate a dynamics problem in a suitable manner so that the wrenches can be computed efficiently. A new constraint wrench formulation for closed-loop systems is presented in this paper using two-level recursions, namely, subsystem level and body level. A subsystem is referred here as the serial- or tree-type branches of a spanning tree obtained by cutting the appropriate joints of the closed loops of the system at hand. For each subsystem, unconstrained Newton–Euler equations of motion are systematically reduced to a minimal set in terms of the Lagrange multipliers representing the constraint wrenches at the cut joints and the driving torques/forces provided by the actuators. The set of unknown Lagrange multipliers and the driving torques/forces associated to all subsystems are solved in a recursive fashion using the concepts of a determinate subsystem. Next, the constraint forces and moments at the uncut joints of each subsystem are calculated recursively from one body to another. Effectiveness of the proposed algorithm is illustrated using a multiloop planar carpet scraping machine and the spatial RSSR (where R and S stand for revolute and spherical, respectively) mechanism.

scholarly journals Interaction Prediction Optimization in Multidisciplinary Design Optimization Problems

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Debiao Meng ◽  
Xiaoling Zhang ◽  
Hong-Zhong Huang ◽  
Zhonglai Wang ◽  
Huanwei Xu
Keyword(s):  
Interaction Design ◽  
Large Scale ◽  
Optimization Problems ◽  
Collaborative Optimization ◽  
System Level ◽  
Design Parameters ◽  
Large Scale Systems ◽  
Interaction Prediction ◽  
Design Variables ◽  
Subsystem Level

The distributed strategy of Collaborative Optimization (CO) is suitable for large-scale engineering systems. However, it is hard for CO to converge when there is a high level coupled dimension. Furthermore, the discipline objectives cannot be considered in each discipline optimization problem. In this paper, one large-scale systems control strategy, the interaction prediction method (IPM), is introduced to enhance CO. IPM is utilized for controlling subsystems and coordinating the produce process in large-scale systems originally. We combine the strategy of IPM with CO and propose the Interaction Prediction Optimization (IPO) method to solve MDO problems. As a hierarchical strategy, there are a system level and a subsystem level in IPO. The interaction design variables (including shared design variables and linking design variables) are operated at the system level and assigned to the subsystem level as design parameters. Each discipline objective is considered and optimized at the subsystem level simultaneously. The values of design variables are transported between system level and subsystem level. The compatibility constraints are replaced with the enhanced compatibility constraints to reduce the dimension of design variables in compatibility constraints. Two examples are presented to show the potential application of IPO for MDO.

A Multidisciplinary and Multiobjective System Analysis and Optimization Methodology for Embedding Integrated Systems Health Management (ISHM) Into NASA’s Complex Systems

2006 ◽  
Author(s):  
Ali Farhang Mehr ◽  
Irem Y. Tumer
Keyword(s):  
System Analysis ◽  
Health Management ◽  
Space Mission ◽  
Shared Values ◽  
System Level ◽  
Integrated Systems ◽  
Subsystem Level ◽  
Optimization Methodology ◽  
Design Protocol ◽  
Component Failures

NASA’s future space exploration systems will include a highly complex Integrated Systems Health Management (ISHM) capability, which can detect, predict, isolate and respond to system and component failures in order to improve safety and maintainability. An ISHM system, as a whole, consists of several subsystems that monitor different components of a space mission. Due to the complex and multidisciplinary nature of designing ISHM, there seems to be a lack of formal methodologies to design an optimal (or near-optimal) ISHM for a given system of systems. In this research, we propose a new methodology to design and optimize ISHM as a distributed system with multiple interacting disciplines as well as multiple conflicting design objectives (i.e. Figures Of Merit or FOMs). This specialized multidisciplinary design approach can be used to optimize the effectiveness of ISHM systems for future NASA missions. We assume a hierarchical design protocol, where each subsystem communicates with other subsystems only in a top-down tree structure. At the top level, the overall performance of the mission consists of system-level variables, parameters, objectives, and constraints that are shared throughout the system and by all subsystems. Each subsystem will then comprise of these shared values in addition to those values that are specific to subsystems. As a specific case study, we take the example of designing an ISHM capability for X-34 reusable launch vehicle in two levels. The proposed approach, referred to as ISHM Multidisciplinary and Multiobjective System Analysis & Optimization (or ISHM MMSA&O), has a hierarchical structure to pass up or down shared values between the two levels with system-level and subsystem-level optimization routines.

scholarly journals Robust decentralized controller design in time domain: Equivalent subsystem approach

2021 ◽  
Vol 72 (5) ◽  
pp. 330-336
Author(s):  
Vojtech Veselý
Keyword(s):  
Complex System ◽  
Large Scale ◽  
Controller Design ◽  
Linear Time ◽  
Dynamic Properties ◽  
Design Procedure ◽  
Uncertain System ◽  
Original Method ◽  
Pole Placement ◽  
Subsystem Level

Abstract In this paper, the original method to design of PID robust decentralized controller is obtained for linear time-invariant large-scale uncertain system. The controller design procedure performs on the subsystem level such that the closed-loop stability and performance of complex system in the frame of the designer chosen controller design procedure ( H 2 , L 2 -gain, pole placement,...) is guaranteed. The proposed method is implemented in two steps. In the first step, the required dynamic properties of the subsystems are determined so as to ensure the stability of complex system. In the second step, on the subsystem level a decentralized controller design is provided using any suitable design procedure for each subsystem.

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