Search results for " control system"
showing 10 items of 262 documents
Vibration control for adjacent structures using local state information
2014
In this paper, a novel strategy for structural vibration control of multi-structure systems is presented. This strategy pays particular attention to mitigating negative interstructure interactions. Moreover, it is based on recent advances in static output–feedback control, which make possible the efficient computation of decentralized velocity-feedback controllers by solving a single-step optimization problem with Linear Matrix Inequality constraints. To illustrate the main ideas, a local velocity-feedback energy-to-peak controller is designed for the seismic protection of a two-building system. This controller is remarkably effective and extremely simple. Moreover, it can also be implement…
Passive-damping design for vibration control of large structures
2013
In this work, a systematic strategy to design passive damping systems for structural vibration control is presented. The proposed design methodology is based on the equivalence between decentralized static velocity-feedback controllers and passive damping systems. By using recent developments in static output-feedback control, the design of passivedamping systems can be formulated as a single optimization problem with Linear Matrix Inequality constraints. Moreover, this optimization problem can be efficiently solved with standard numerical tools, even for large dimension systems. Due to its computational effectiveness, the proposed methodology can be applied to the design of passive damping…
The sROD demonstrator for the ATLAS Tile Calorimeter Upgrade
2012
This work presents the early design of the super Read-Out Driver (sROD) demonstrator board for the Tile Calorimeter Demonstrator project. This project aims to test the new readout electronics architecture for the Phase 2 Upgrade of the ATLAS Tile Calorimeter, replacing the front-end electronics of one complete drawer with the new electronics during the Long Shutdown 2013, in order to evaluate its performance. The sROD demonstrator board will receive and process data from 48 channels. Moreover the sROD demonstrator board will send preprocessed data to the present trigger system, and will transmit trigger control and timing information (TTC) and Detector Control System (DCS) commands to the f…
SELF-TUNING FUZZY CONTROL OF A ROTARY DRYER
2002
Abstract Drying, especially rotary drying is without doubt one of the oldest and most common unit operations in industries. It is a very complex non-linear process including the movement of solids in addition to thermal drying. This means that both the modelling and control of a rotary dryer is difficult with conventional methods. The aim of this research was to improve dryer control by developing control systems based on self-tuning PID-type fuzzy logic controllers. The behaviour of the control systems has been tested with simulations based on the model of a pilot plant dryer located in the Control Engineering Laboratory at the University of Oulu. The control results have been compared ach…
AGILITY AND THE ROLE OF PROJECT — INTERNAL CONTROL SYSTEMS FOR INNOVATION PROJECT PERFORMANCE
2019
As a reaction to the rapidly changing environment, organisations increasingly use agile project management (APM) methods to develop innovation. The associated process changes necessitate the adaption of organisational structures and control systems. This study draws on Simon’s Levers-of-Control framework (LOC) to explore the impact of different control levers on innovation project performance. Based on a survey of 316 project managers and product owners, the results suggest that the use of interactive project control systems and project-internal belief systems has a positive impact on the innovation outcome, regardless of the degree of agility of the project. Furthermore, we reveal that a s…
Lighting control systems: Factors affecting energy savings' evaluation
2015
Abstract The use of automated lighting control systems allows to reduce lighting costs and to achieve significant energy savings. The energy performances of controls are affected by many factors, the impact of which is very difficult to account for during the design process. The goal of this paper is to describe the factors that influence the control systems’ energy performances, to analyze how the currently available calculation tools take them into account and finally to propose a simple method to adjust results obtained from the simulation software.
Hidden oscillations in aircraft flight control system with input saturation
2013
Abstract The presence of actuator saturation can dramatically degrade the system performance. Since the feedback loop is broken when the actuator saturates the unstable modes of the regulator may then drift to undesirable values. The consequences are that undesired nonlinear oscillations appear and that the settling time may unacceptably increase. Rigorous analysis of nonlinear aircraft models is a very difficult task, that is why a numerical simulation is often used as an analysis and design tool. In this paper difficulties of numerical analysis related to the existence of hidden oscillations in the aircraft control system are demonstrated.
Type-2 fuzzy control of a fed-batch fermentation reactor
2010
Abstract The aim of the paper is to present the application of type-2 fuzzy logic controllers (T2FLCs) to the control of a fed-batch fermentation reactor in which the penicillin production is carried out. The performance of the control system using T2FLCs is compared by simulation with that of a control system using type-1 fuzzy logic controllers (T1FLCs). The non linear model used for the simulation study is an unstructured model characterized by the presence of non linearities, parameter uncertainty and measurement noise. Simulation results confirm the robustness of the T2FLC which shows a better performance than its type-1 counterpart particularly when uncertainties are present in the co…
Control of the Biodegradation of Mixed Wastes in a Continuous Bioreactor by a Type-2 Fuzzy Logic Controller
2009
Abstract Type-2 fuzzy logic control is proposed for nonlinear processes characterized by bifurcations. A control simulation study was conducted for a bioreactor with cell recycle containing phenol and glucose as carbon and energy sources in which a pure culture of Pseudomonas putida is carried out. The model developed by Ajbar [Ajbar, A. (2001). Stability analysis of the biodegradation of mixed wastes in a continuous bioreactor with cell recycle. Water Research, 35 (5), 1201–1208] was used for the simulations. The particular dynamics of the bioreactor, characterized by two saddle-node bifurcations, makes its control difficult, since it may become unstable also for small variations of some p…
A New Web Interface for Distributed Control Systems: Application to the Chemical Monitoring of a Wort Fermentation Process
2006
A new web interface for rule net-based distributed control systems is proposed. It is applied to the monitoring of a chemical analysis system coupled with a wort fermentation process. A complete description of both the chemical and the informatics system is presented. This interface offers the possibility of accessing the process from any Internet-connected device (PC, PDA, etc.), using a standard browser as the only software required. The evolution of the results obtained in the FIA monitoring (and consequently of the process) can be analyzed by means of this interface; on the other hand, the process itself can be directly controlled through the modification of the different working parame…