1,726,124 research outputs found
Decentralized control of ecological and biological networks through Evolutionary Network Control
Full text linkEvolutionary Network Control (ENC) has been recently introduced to allow the control of any kind of ecological and biological networks, with an arbitrary number of nodes and links, acting from inside and/or outside. To date, ENC has been applied using a centralized approach where an arbitrary number of network nodes and links could be tamed. This approach has shown to be effective in the control of ecological and biological networks. However a decentralized control, where only one node and the correspondent input/output links are controlled, could be more economic from a computational viewpoint, in particular when the network is very large (i.e. big data). In this view, ENC is upgraded here to realize the decentralized control of ecological and biological nets
Decentralized Control of Multi-Agent Dynamic Games
No full textRecent studies in game-theory provided ways to steer multi-agent games to their Nash equilibrium by means of a decentralized approach. However, these approaches have not considered the internal dynamics of the individual agents. This thesis work provides decentralized control methods to account for these internal dynamics whilst ensuring that the overall system still reaches the Nash equilibrium.Mechanical Engineering | Systems and Contro
Distributed control design for underwater vehicles
No full textThe vast majority of control applications are based on non-interacting decentralized control designs. Because of their single-loop structure, these controllers cannot suppress interactions of the system. It would be useful to tackle the undesirable effects of the interactions at the design stage. A novel model predictive control scheme based on Nash optimality is presented to achieve this goal. In this algorithm, the control problem is decomposed into that of several small-coupled mixed integer optimisation problems. The relevant computational convergence, closed-loop performance and the effect of communication failures on the closed-loop behaviour are analysed. Simulation results are presented to illustrate the effectiveness and practicality of the proposed control algorithm
Stability and Decentralized Control of Plug-and-Play DC Distribution Grids
No full textChanges in distribution grids pose significant challenges with respect to the control and management of these grids. Stability and decentralized control are vital to ensure the availability and accessibility of plug-and-play dc distribution grids that are (temporarily) without communication. Therefore, this paper presents guidelines for these grids that ensure global stability and a decentralized control strategy that implements these stability guidelines. The stability guidelines are derived using a Brayton-Moser representation of the system to arrive at a Lyapunov candidate function. Furthermore, the decentralized control strategy implements these stability guidelines and ensures that the voltages in the system remain within a specified range. Additionally, several simulations are performed to illustrate the stability of the system and the behavior of the control strategy under different scenarios.DC systems, Energy conversion & StorageAlgorithmic
Optimization of CPG-network for decentralized control of a snake-like robot
No full textPeriodic locomotion of animal bodies with large degree of freedom is known to be realized by decentralized control using network of central pattern generators (CPGs) that are distributed in spinal cord (in vertebrates) or nerve cords (in invertebrates). In this paper, optimization of a decentralized controller for a snake-like robot based on CPG-network is presented. The controller is composed of CPGs on every robot joints and connections between them. Oscillations of CPGs are coordinated by propagating them each other. For several types of network structure, genetic algorithm (GA) is used to optimize neural parameters, i.e. CPG parameters and synaptic weights. As a result, we derived a CPG-network that is optimal in terms of moving spee
A Weak Structural Approach to Decentralized Control
No full textThe research discussed here explores the interplay between dynamical structure functions, the communication structure of a controller and the zero pattern of a controller. Precisely understanding this interplay is a necessary result to utilize dynamical structure functions to help broaden the known tractable class of decentralized control problems. The long term goal of this research is to broaden the set of tractable convex decentralized control problems by utilizing the structure encapsulated in dynamical structure functions. The research highlighted here was presented during the 2010 BYU Spring research conference and published in detail as my undergraduate honors thesis “Decentralized Control Problems: a weak structural approach”. Characterizing tractable decentralized control problems is difficult. Characterizing tractable decentralized control problems means to identify a set of decentralized control problems for which designing an optimal stabilizing controller is tractable1. Hopefully, a convenient check or condition is available to determine if an arbitrary set of problems is a subset of the ones shown to be tractable
Decentralized control with communication between controllers
Full text linkThe paper presents the problem of decentralized control with communication between controllers. It differs from the regularly considered decentralized control problem in that the controllers can communicate information. Major questions are then: What? When? and To Whom? to communicate information. The problem instances of decentralized control with communication between controllers for discrete-event systems and for finite-dimensional linear systems are described in detail
Six-axis decentralized control design for spacecraft formation flying mission
Full text linkThis contribution addresses the control design for
the three-spacecraft formation flying interferometry mission Pegase. The operational mode considered is the high-precision nulling phase. The control design has as major objective the minimization of the variance of the controlled outputs, e.g. the optical path difference. The payload performance demands are shown to be fulfilled in spite of orbital disturbances, solar radiation pressure as well as sensor and actuator noise. Furthermore, a novel iterative algorithm is proposed, capable of designing decentralized H2-suboptimal controllers. These controllers consist of a set of individual closed loops on board the different spacecraft which only use locally available
measurements, forces and torques. This approach reduces
communication bandwidth and enhances robustness concerning
faulty communication links. Finally, the performance loss due to decentralization is investigated
Decentralized Control of Unmanned Aerial Robots for Wireless Airborne Communication Networks
Full text linkThis paper presents a cooperative control strategy for a team of aerial robotic vehicles to establish wireless airborne communication networks between distributed heterogeneous vehicles. Each aerial robot serves as a flying mobile sensor performing a reconfigurable communication relay node which enabls communication networks with static or slow-moving nodes on gorund or ocean. For distributed optimal deployment of the aerial vehicles for communication networks, an adaptive hill-climbing type decentralized control algorithm is developed to seek out local extremum for optimal localization of the vehicles. The sensor networks estabilished by the decentralized cooperative control approach can adopt its configuraiton in response to signal strength as the function of the relative distance between the autonomous aerial robots and distributed sensor nodes in the sensed environment. Simulation studies are conducted to evaluate the effectiveness of the proposed decentralized cooperative control technique for robust communication networks
Aeroelastic Wing Demonstrator with a Distributed and Decentralized Control Architecture
No full textThis study investigated the design and development of an autonomous aeroservoelastic wing concept with distributed flaps. This wing demonstrator was developed in the scope of the SmartX project, aiming to demonstrate in-flight performance optimization and multi-objective control with over-actuated wing designs. Following a successful test campaign with a previous wing design based on active morphing, this study aims to develop an over-actuated aeroelastic wing design suitable for aeroelastic control, including flutter suppression, maneuver and gust load alleviation. A decentralized control architecture is developed for the over-actuated and over-sensed system, allowing efficient sensing data processing and control algorithms. Aerodynamic and structural analyses are performed to determine actuator torque requirements and actuation mechanism design. Furthermore, buckling analysis is performed to size the wing structure. A state-space aeroelastic dynamic model is established to analyze the gust response and control effectiveness of the wing. It is established that a linear quadratic regulator significantly improves the closed-loop performance. Furthermore, the hypotheses are confirmed that fast actuation improves load alleviation performance and high-frequency disturbance rejection effectiveness. The manufacturing and integration of the wing demonstrator are discussed, which lay a foundation for future static and dynamic wind-tunnel experiments.Arts & CraftsAerospace Structures & Computational Mechanic
- …
