Real Time Control

We develop a multiscale simulation method for dense granular drainage, based on the recently proposed spot model, where the particle packing flows by local collective displacements in response to diffusing "spots" of interstitial free volume. By comparing with discrete-element method (DEM) simulations of 55,000 spheres in a rectangular silo, we show that the spot simulation is able to approximately capture many features of drainage, such as packing statistics, particle mixing, and flow profiles. The spot simulation runs two to three orders of magnitude faster than DEM, making it an appropriate method for real-time control or optimization. We demonstrate extensions for modeling particle heaping and avalanching at the free surface, and for simulating the boundary layers of slower flow near walls. We show that the spot simulations are robust and flexible, by demonstrating that they can be used in both event-driven and fixed timestep approaches, and showing that the elastic relaxation step used in the model can be applied much less frequently and still create good results.

This work addresses the real time control of the Khepera mobile robot [1] navigation in a maze with reflector walls. Boolean Neural Networks such as RAM [2] and GSN [3] models are applied to drive the vehicle, following a light source, while avoiding obstacles. Both neural networks are implemented with simple logic and arithmetic functions (NOT, AND, OR, Addition, and Comparison), aiming to improve system speed. The results obtained are compared with two other control strategies: Multi-layer Perceptron (MLP) [4] and Fuzzy Logic [5].

Real time database transactions must satisfy database consistency as well as timing constraints. Timing constraints are defined in terms of deadline. Numbers of algorithms are proposed to schedule real time database transactions in order to increase the overall performance of the disk. In this paper, we have proposed a new approach based on Two-way scan algorithm which gives better result than Two-way scan. In our new approach, Shortest Seek Time (SST) groups are formed like Two-way scan and then priority is assign to each transaction. Transaction having lowest priority value is served first. Consecutive groups are served one after the other. Transactions are served only if they are feasible.

A glimpse on the present status of ion track technology is provided: irradiation, etching and electro-replication of single and multiple ion tracks. The uses of an electrolytic cell for single and counted track studies are sketched. In connection with a data acquisition system such a device enables to determine in real-time: track and bulk etch rate, cone angle, and size. Processing can be terminated at a preset time, current, diameter, or length (of wires). The system can be used to rapidly screen new track materials, etchants, and electro-replication processes.

This paper analyses control computation latency and jitter, which have been largely ignored in the control community for real-time (RT) control. The focus is on RT control systems with multiple control tasks running on a uniprocessor. Three strategies are proposed to reduce control latency and/or jitter: introduction of offsets into control task scheduling, decomposition of control tasks; and increasing the priority levels of output subtasks. Examples are given to demonstrate the effectiveness of the proposed methods.

The purpose of the paper is to illustrate the remote control of hardware in the laboratory for educational purposes, using commercial off-the-shelf equipment and available freeware. The goal is to eliminate extensive programming using high-level languages, such as Java programming to achieve remote connectivity, and focus on the primary task of implementing control algorithms. The use of MS NetMeeting for Internet-based control is described. Control experiments were easily carried out by a remote user, using Matlab-based real-time tools and MS NetMeeting.

The research in this paper deals with the simulation of continuous machine systems that can be described in a discrete manner (discrete-event systems), using qualitative simulation techniques. In order to represent discrete-time descriptions of machine systems and processes in an efficient way, this approach uses a combination of both qualitative modelling techniques and numerical methods. An objectoriented qualitative modelling and simulation toolbox, called QMTOOL, was extended and applied into modelling specific machine processes. Experiments carried out using this qualitative modelling and simulation toolbox, provided performance metrics and assisted the design and real-time control of specific industrial machines and processes. The results obtained have shown that qualitative modelling can provide less complex computational models for describing and simulating discrete-event machine systems, and that these models could be applied in cases where traditional mathematical models are difficult to manage.

This paper represents an ongoing investigation of dexterous and natural control of upper extremity prostheses using the myoelectric signal (MES). The scheme described within uses pattern recognition to process four channels of MES, with the task of discriminating multiple classes of limb movement. The method does not require segmentation of the MES data, allowing a continuous stream of class decisions to be delivered to a prosthetic device. It is shown in this paper that, by exploiting the processing power inherent in current computing systems, substantial gains in classifier accuracy and response time are possible. Other important characteristics for prosthetic control systems are met as well. Due to the fact that the classifier learns the muscle activation patterns for each desired class for each individual, a natural control actuation results. The continuous decision stream allows complex sequences of manipulation involving multiple joints to be performed without interruption. Finally, minimal storage capacity is required, which is an important factor in embedded control systems.

Many dynamic simulators have been developed in the last thirty years for different types of vehicles. Flight simulators and drive simulators are very well known examples. This paper describes the design and implementation of a dynamic simulator for the testing of inertial sensors devoted to vehicle navigation through a Hardware-In-The-Loop test rig composed of an industrial robot and a commercially available Inertial Measurement Unit (IMU). The authors are developing an innovative localization algorithm for railway vehicles which integrates inertial sensors with tachometers. The opportunity to set up a testing simulator capable of replicating in a realistic fashion the dynamic effects of the vehicle motion on inertial sensors allows to avoid expensive on board acquisitions and to speed up algorithm tuning. The real-time control architecture featured by the available industrial robot allows to precisely specify and execute motion trajectories with tight path and time law constraints required by the application at hand.

In an effort to find a better suited interface for musical performance, a novel approach has been discovered and developed. At the heart of this approach is the concept of physical interaction with sound in space, where sound processing occurs at various 3-D locations and sending sound signals from one area to another is based on physical models of sound propagation. The control is based on a gestural vocabulary that is familiar to users, involving natural spatial interaction such as translating, rotating, and pointing in 3-D. This research presents a framework to deal with realtime control of 3-D audio, and describes how to construct audio scenes to accomplish various musical tasks. The generality and effectiveness of this approach has enabled us to reimplement several conventional applications, with the benefit of a substantially more powerful interface, and has further led to the conceptualization of several novel applications.

In this paper we propose a general purpose hardware/software environment for hard real time simulation of dynamical systems in the context of control engineering. With this system, realistic analysis and tests can be carried out for controller algorithms characterized by time determinism with strict restrictions, multiple inputs and multiple outputs and based on robust control theory. A hard real time

A comprehensive study of capacitor placements and real-time control in general unbalanced distribution systems is undertaken. New developments in a loss reduction formula, problem formulations, solution methodology and mathematical justification are presented. The problem is decoupled into two subproblems: the capacitor placement subproblem and the real-time control subproblem. An effective solution algorithm for placing capacitors and determining their real-time control

Fuzzy logic control is one of the most interesting fields where fuzzy theory can be effectively applied. Fuzzy logic techniques attempt to imitate human thought processes in technical environments. In doing so, the fuzzy logic approach allows the designer to handle ...

In this paper, we present a solution and experimental results for real-time control of manipulation tasks considering the alignment of a robots end effector relative to some reference. The developed controller is applicable to industrial manipulators and is based on the pseudoinverse redundancy resolution method. The application considered is the employment of two industrial robots in an offshore remote inspection and maintenance system. A leader robot is controlled freely from onshore, and a follower robot uses an attached camera to provide the onshore operator with live video feed of the ongoing operation. Robot manipulators constitute flexible camera platforms, compared to e.g. simple pan/tilt units, for monitoring offshore operations. We develop a controller for the follower robot such that automatic camera tracking is achieved using pseudoinverse redundancy resolution control. A minimal task space parametrization relying on stereographic projection is constructed which achieves relative end effector alignment tracking without introducing representational or algorithmic singularities. It is shown that singular configurations will only in special cases affect the closed loop behavior. The controller is applicable to tasks such as spray painting or polishing on curved surfaces. The control approach is experimentally validated on two Kuka KR-16 industrial robot manipulators.

In the present study the two-way shape memory effect (TWSME) of a Ni-51 at.% Ti alloy was investigated and a numerical model, able to simulate its hysteretic behaviour in the strain-temperature response, is proposed. In particular, the TWSME was induced through a proper thermo-mechanical training, carried out at increasing number of training cycles and for two values of training deformation, and the thermal hysteretic behaviour, between M f (Martensite finish temperature) and A f (Austenite finish temperature), was recorded. The experimental measurements were used to develop a phenomenological model, based on the Prandtl-Ishlinksii hysteresis operator, which was implemented in a Matlab ® function and a Simulink ® model. A systematic comparison between experimental results and numerical predictions is illustrated and a satisfactory accuracy and efficiency has been observed, therefore the method looks suitable for realtime control of NiTi based actuators.

Real-time control applications will benefit in the near future from the enhanced performance provided by multi-core processor architectures. Nevertheless real-time communication will continue to be critical in distributed plasma control systems where the plant under control typically is distributed over a wide area. At RFX-mod real-time communication is crucial for hard real-time plasma control, due to the distributed architecture of the system, which consists of several VMEbus stations. The system runs under VxWorks and uses Gigabit Ethernet for sub-millisecond real-time communication. To optimize communication in the system, a set of detailed measurements has been carried out on the target platforms (Motorola MVME5100 and MVME5500) using either the VxWorks User Datagram Protocol (UDP) stack or raw communication based on the data link layer.

With the increasing interest in Micro-Electro-Mechanical Systems (MEMS) it is likely that they will be massively deployed in future control systems. Their use raises many new challenges: generic ones and more specific ones depending on the field of application. Considering control systems made of calculators and passive components (actuators and sensors), we have started investigating dependable communication allowing to integrate MEMS on a large-scale (or MEMS network), as for example thousands of micro-actuators acting as a substitute for a current actuator. These changes require to define, to evaluate and to validate new communication systems in terms of architectures and protocols, and consequently their dependability so that the future control systems will be as much dependable as the current ones. In this prospect, we will first define solutions for control systems without MEMS. This article presents the first steps of our work. After a brief description of the kind of systems...

In recent trends, digital information to the industrial integration for the intelligent transportation system (ITS) field is gaining importance for the researcher, academia, and industrial persons. Visual information helps to manage traffic systems in the industrial forum to build smart cities in developed countries. This paper presents vision-based real-time vehicle detection and Vehicle Speed Measurement (VSM) using morphology operation and binary logical process for an unplanned traffic scenario using image processing techniques. Vehicle detection and VSM help to reduce the number of accidents and improve road network efficiency. The bounding box size for vehicle detection is flexible according to vehicles' sizes on the road. We test this system with different colors and dimensions for a selected Region of Interest (ROI). The ROI sets using the two-line approach. Here, we compare the proposed system with the inter-frame difference method and the blob analysis method with recall, precision, and F1 performance parameters.

This paper describes the use of fuzzy logic techniques to control the speed of a three-phase induction motor. The use of Matlab/Simulink and fuzzyTECH MCU96 as software development tools for system design is emphasised. Hardware implementation is based on a standard 16/32-bit microcontroller, without the need of any additional components for the fuzzy logic controller. The system performance is evaluated in comparison with a traditional PI control scheme. Both simulation and experimental results are presented. ᭧

In this article, after describing a procedure to construct trajectories for a spacecraft in the four-body model, a method to correct the trajectory violations is presented. To construct the trajectories, periodic orbits as the solutions of the three-body problem are used. On the other hand, the bicircular model based on the Sun-Earth rotating frame governs the dynamics of the spacecraft and other bodies. A periodic orbit around the first libration-point L 1 is the destination of the mission which is one of the equilibrium points in the Sun-Earth/Moon three-body problem. In the way to reach such a far destination, there are a lot of disturbances such as solar radiation and winds that make the plans untrustworthy. However, the solar radiation pressure is considered in the system dynamics. To prevail over these difficulties, considering the whole transfer problem as an optimal control problem makes the designer to be able to correct the unavoidable violations from the pre-designed trajectory and strategies. The optimal control problem is solved by a direct method, transcribing it into a nonlinear programming problem. This transcription gives an unperturbed optimal trajectory and its sensitivities with respect perturbations. Modeling these perturbations as parameters embedded in a parametric optimal control problem, one can take advantage of the parametric sensitivity analysis of nonlinear programming problem to recalculate the optimal trajectory with a very smaller amount of computation costs. This is obtained by evaluating a first-order Taylor expansion of the perturbed solution in an iterative process which is aimed to achieve an admissible solution. At the end, the numerical results show the applicability of the presented method.

In this paper, the design and implementation of an effective neural network model for turning process identification as well as a neural network controller to track a desired vibration level of the turning machine is as an example of using the neural network for manufacturing process control. Multi -Layer Perceptron (MLP) neural network architecture with Levenberg Marquardt (LM) algorithm has been utilized to train the turning process identifier. Two different strategies have been used for training turning process identifier, and for training the controller model, where there is no mathematical model till now could relate the vibration level to the input turning process parameters "feed, speed, and depth of cut". The vibration signal obtained by the experimental work has been used to train a neural network for identification and control of the turning process. The developed Neuro -controller has been checked by applying different reference vibration signals where it is found that the controller has good ability to track the reference within maximum settling time that does not exceed (4 sec for 95% of the signal); maximum overshot not exceed (30%) of the reference signal used for checking.

In the last years design procedures of urban drainage systems have shifted from end of pipe design criteria to ambient water quality approaches requiring integrated models of the system for evaluation of measures. Emphasis is put on the improvement of the receiving water quality and the overall management of river basins, which is a core element of the Water Framework Directive (WFD) as well.

This paper presents a fault-tolerant distributed system designed for real-time control applications (REBUS), which is one of the research basis of the industrial real-time system MODUMAT 800. It is made up of functional units, i.e., programmable multiloop regulators and operator displays, linked together by a communication structure. The communication hardware consists of a set of serial bus interface boards, one per functional unit, loosely coupled together by a double serial bus and linked to their functional units by a private parallel bus.

The paper concerns Drag-Free and Attitude Control of the European satellite Gravity field and steady-state Ocean Circulation Explorer (GOCE) during the science phase. Design has followed Embedded Model Control, where a spacecraft/environment discrete-time model becomes the realtime control core and is interfaced to actuators and sensors via tuneable feedback laws. Drag-free control implies cancelling non-gravitational forces and all torques, leaving the satellite to free fall subject only to gravity. In addition, for reasons of science, the spacecraft must be carefully aligned to the local orbital frame, retrieved from range and rate of a Global Positioning System receiver. Accurate drag-free and attitude control requires proportional and low-noise thrusting, which in turn raises the problem of propellant saving. Six-axis drag-free control is driven by accurate acceleration measurements provided by the mission payload. Their angular components must be combined with the star-tracker attitude so as to compensate accelerometer drift. Simulated results are presented and discussed. he contributed to data reduction of the European astrometric mission Hipparcos. Technological studies in view of scientific and drag-free space missions, like Gaia and GOCE provided the opportunity of applying Embedded Model Control to drag-free satellites and to electro-optics. He contributed to the conception, design and implementation of the interferometric thrust-stand Nanobalance, capable of sub-micro-Newton accuracy. His research interests cover the entire field of control problems that are challenging because of complexity, uncertainty and precision.

We investigate the dripping of liquids around solid surfaces in the regime of inertial flows, a situation commonly encountered with the so-called "teapot effect". We demonstrate that surface wettability is an unexpected key factor in controlling flow separation and dripping, the latter being completely suppressed in the limit of superhydrophobic substrates. This unforeseen coupling is rationalized in terms of a novel hydro-capillary adhesion framework, which couples inertial flows to surface wettability effects. This description of flow separation successfully captures the observed dependence on the various experimental parameters - wettability, flow velocity, solid surface edge curvature-. As a further illustration of this coupling, a real-time control of dripping is demonstrated using electro-wetting for contact angle actuation. Comment: 4 pages; movies at http://lpmcn.univ-lyon1.fr/~lbocquet

Fuel Cell Hybrid Electric Vehicles (FCHEV) are being investigated in many research and development programs motivated by the urgent need for more fuel-efficient vehicles that produce fewer harmful emissions. Hybridization can greatly benefit fuel cell technology. There are many potential ad vantages such as the improvement of transient power demand, the ability of regenerative braking and the opportunities for optimization of the vehicle efficiency. The coordination among the various power sources requires a high level of control in the vehicle. This work presents a control system that fulfils the power demanded by the electric motor making use of two power sources: a primary source (fuel cell) and a battery pack. Both power sources, independently or together, supply power to the vehicle in order to satisfy driver's demand. The real-time control computes the power distribution between the primary energy source and its associated Energy Storage System (ESS) to optimize the global hydrogen consumption while maintaining drivability. The coordination between the various power sources requires a high level of control in the vehicle. Model Predictive Control (MPC) is used in order to minimize the overall energy use in the presence of several constraints that appear due to drivability requirements and the characteristic of the components. The proposed control strategy has been tested on a simulated model of a SUV (Sport Utility Vehicle), showing that a good control strategy can fulfil the power requested by the driver with the minimum fuel consumption.

The described MoSART environment is shown to be useful for analyzing, designing, visualizing, and evaluating control systems for a class of "cart-pendulum" electromechanical systems. The environment-referred to as Cart-Pendulum Control3D-Lab-is based on Microsoft Windows, Visual C++, Direct-3D, and MATLAB/Simulink. The environment can be used as a stand-alone application or together with MATLAB, Simulink, and toolboxes. When used as a stand-alone application, a friendly graphical user interface permits easy interaction. Users may select (via pull-down menus) systems, dynamical models, control laws, exogenous signals (including joystick inputs) and associated parameters, initial conditions, integration routines, and associated parameters. When used with MATLAB, Simulink, and toolboxes, the previously mentioned nominal features are significantly enhanced. In either case, the interface permits users to access the following (via pull-down menus): animation models, mesh properties, texture and lighting models, system-specific visual indicators, graphics to be displayed, animation/data display/storage rates, simulation control buttons, and extensive documentation. When Simulink is present, users can exploit extensive visualization and three-dimensional (3-D) animation features through provided and/or user-generated Simulink diagrams. This capability makes the developed environment very extensible with respect to mathematical models and control laws. In addition, users may readily export simulation data to MATLAB/toolboxes for postprocessing and further analysis. The environment also contains a suite of well-documented (easy-to-modify) models and control laws that are implemented within the provided Simulink block diagrams. Provided (special) blocks enable animation, joystick inputs, and (near) real-time simulation and animation (when possible). (Near real-time-or faster-than-real-time-simulation and animation are possible whenever the mathematical and animation models are sufficiently simple and data manipulation requirements, e.g. storage and display, are sufficiently mild. For the systems considered, (near) real-time simulation and animation is readily achievable.) Associated with each block diagram are system-specific, menu-accessed m-files that permit detailed analysis and design. A hardware module permits real-time control of actual hardware experiments. The developed environment is shown to be a valuable tool for enhancing both controls education in a variety of classes as well as research. Examples are presented to illustrate the utility of the environment.

The paper provides an overview of the agent-based solutions developed by the Rockwell Automation company for the purposes of industrial control. Using agent-based manufacturing control, a higher degree of flexibility and reconfigurability of manufacturing solutions as well as higher robustness of the industrial systems can be achieved. Specific solutions connected with the proposed agent architecture, with implementation of the real-time control agents as well as with the information transfer among the SW agents and the real-time agents in a Programmable Logic Controller (PLC) are presented. Attention is also paid to the simulation of both the agent-based manufacturing facilities and their control systems. A simulation environment MAST for material handling systems has been implemented in JADE. The opportunity to re-use directly the simulation software on the agent control level is one of the most important features of MAST.

Embedded control systems are becoming ubiquitous in control applications. They combine the properties of computer embedded system with newly designed complex controllers where flexible, safe and reconfigurable operations are required. The aim of this paper is to grasp the main features of these systems, analyse the main problems and present some solutions already developed by the authors. A new concept on the control kernel of an application is also introduced and some conclusions are drafted.

3) Calculate a new control input that minimizes the cost function, 4) Repeat steps 2 and 3 until desired minimization is achieved, 5) Send the first control input, to the plant, 6) Repeat entire process for each time step. The computational performance of a GPC implementation is ...

the AC drives direct torque control (DTC) is used to obtain high performance decoupled torque and flux control. The SVM based direct torque control is a common solution which used to solve the conventional DTC's problems such as the high torque ripples and variable switching frequency. However, this control technique bases on stator flux orientation and PI controllers. This paper aims to improve the SVM-DTC performance by replacing the PI controllers by high order sliding mode controllers. Theses controllers are based on second order super twisting strategy, they can overcome the classical PI problems which are represented in robustness against parameters variation and external disturbance. Furthermore, super twisting algorithm reduces the chattering effect and keep the same properties of the first order sliding mode control. Another point, this paper presents a design of load torque observer based on second order sliding mode control in order to estimate the load value and reduce the cost and the uncertainties of control system. The simulation and experimental results of robust SVM-DTC control method are presented using Matlab/Simulink with real time interface using dSpace 1104 bored.

This article describes a computational framework, which can run almost on every computer connected to a IP based network, to study teleoperatiort techniques. The paper discussw the teleoperation of a mobile platform from ii remote computer, both connected by the Internet communication network. To obtain a cheap and portable solution, the user interface and communication management was developed using Java language. The development based on this language gave us, a cheap, portable and easily to improve software package that is useful to test new control techniques with large time delays. Since the real time control over Internet can suffer from unpredictable delays and bandwidth constraints, we use the RTP protocol to overconne some of these problems. I. IN'I'RODUCTION Several research groups have recently turned their attention to the develop nent of teleoperated systems due to the every day appearance of new potential applications that can benefit from the use of this kind of solutions. The recent evolution of microprocessors and communication systerns, and the wide availability of simple and cheap solutions using these systems, have also attracted many people .to an area that traditionally was only accessible to restricted groups with strong financial support. Among the applicaiions of teleoperated systems we find those related with the exploration and manipulation in hazardous environments, like nuclear power plants [9, lo]. The research activities in this area are quite diverse, going from the development of communication links, to the search for an optimum user interface for a certain application. Here we can cite some of the major works that have been developed in the recent years: 0 Space applicatiors: NASA JPL labs are developing techniques since the beginning of space exploration. These techniques are being used on the development of a mobile vehicle that will integrate "This work was partially financed by NATO Scientific Affairs Division on the framework of the NATO Science for Stability Program, PO-ROBOT project.

In the European Union, the Water Framework Directive (WFD) enforces a good ecological and chemical status of all surface waters. In-stream (immission) concentrations and populations need to comply with certain standards. In order to deal with this new legislation, integrated urban water management is an important issue. Real-time control (RTC) is one approach that may be used to improve the performance of the system. Immission-based RTC has been suggested as a proper instrument to help fulfilling the WFD requirements. In order to design and tune an immission-based RTC scheme and to judge the overall effect on the receiving water, an integrated mathematical model of the urban wastewater system is necessary. Several problems are encountered when creating such a model and solutions are discussed in this paper. With this integrated model, an immission-based control strategy is developed for a particular case study and is shown to be able to improve the water quality compared to the uncontrolled case. In the final part, the robustness of this control strategy is tested, as an important additional measure of performance. It can be concluded that there are tools available to help dealing with the operational consequences of the WFD.

Real time control of five-axis machine tools requires smooth generation of feed, acceleration and jerk in CNC systems without violating the physical limits of the drives. This paper presents a feed scheduling algorithm for CNC systems to minimize the machining time for five-axis contour machining of sculptured surfaces. The variation of the feed along the five-axis tool-path is expressed in a cubic B-spline form. The velocity, acceleration and jerk limits of the five axes are considered in finding the most optimal feed along the toolpath in order to ensure smooth and linear operation of the servo drives with minimal tracking error. The time optimal feed motion is obtained by iteratively modulating the feed control points of the B-spline to maximize the feed along the tool-path without violating the programmed feed and the drives' physical limits. Long tool-paths are handled efficiently by applying a moving window technique. The improvement in the productivity and linear operation of the five drives is demonstrated with five-axis simulations and experiments on a CNC machine tool. r

In recent years, bus priority techniques for signals controlled by traffic management centers have become a viable alternative to reduce passenger delays at signalized intersections, especially in mixed traffic corridors. However, before any bus signal priority strategy is deployed in such corridors, the impacts on the different users of the system should be evaluated. The main objective of this work was to assess the operational performance of passive and active bus priority techniques in fixed and real-time signal systems of one of the main arterial corridors in Fortaleza, Brazil. As a secondary objective, it also evaluated the operational benefits of a SCOOT adaptive signal control system, comparing it with well-adjusted fixed-time plans optimized by TRANSYT, for periods of medium and high traffic volumes. In the evaluation of alternative scenarios, the
following performance measures were considered: vehicle delay and number of stops simulated by SCOOT, as well as bus and automobile travel times observed in the field during the operation of each scenario. The results did not favor the adoption of passive and active priority schemes in the studied corridor; this led to the conclusion that SCOOT’s real-time control, programmed for a good signal progression of the general traffic (buses and automobiles), is the best signal control strategy for an arterial corridor similar to the one under analysis.

The wall-state of reactive ion etch tools is known to strongly affect etch results, and previous studies show neutral species concentrations vary with chamber seasoning. In this paper, we show the first reported simultaneous measurements of wall-state-induced plasma density and poly-Si etch rate changes, and demonstrate a real-time feedback control system that corrects for the plasma density variation. This eliminates the "first wafer" effect in Cl 2 etching of poly-Si in a Lam 9400 TCP. Contrasting chamber conditions studied include fluorination/cleaning by C 2 F 6 plasmas vs. chlorination/deposition from Cl 2 plasmas. Transient density changes from opposing wall states were measured using a microwave resonance cavity technique called BroadBand RF. Following chamber fluorination, Broadband data show a significant (≥20%) increase in electron plasma frequency during a 60sec Cl 2 etch. Independent sensor measurements correlate strongly with the BroadBand signals, particularly real-time poly-Si etch rate and SiCl 4 etch product concentration. These observed real-time variations were then compensated using a proportional-integral (PI) feedback control algorithm, where BroadBand peak frequency is the control output and TCP power is the controller state variable. Such PI control not only stabilizes BroadBand peak frequencies, but also steadies poly-Si real-time etch rate and SiCl 4 etch product.

A cooling coil unit (CCU) is nonlinear in nature. Existing CCU models for control and optimization are either linear approximations around an operating point or very complex nonlinear ones, resulting in difficulties for real time applications. Therefore, it is of practical importance to develop a simple, yet accurate CCU engineering model that will yield better real time control and optimization of heating, ventilating and air conditioning (HVAC) systems. In this paper, a technique for developing a simple, yet accurate engineering CCU model is presented. The modeling technique is based on an energy balance and heat transfer principles. Commissioning information is then used to estimate, at most, three model parameters by either a linear or nonlinear least squares method. Experiment shows that the method is robust and gives a better match to real performance over the entire operating range when compared to existing methods in the literature. This model is expected to have wide applications in control and optimization of HVAC systems. The modeling methodology can also be extended to other heat exchangers.

In this paper, we present the first step of a project that is able to perform both speech and singing synthesis controlled in real-time. Our aim is to develop a flexible application allowing performers to produce complex and versatile singing–as well as speech–articulations. Thus, we have adapted an existing speech synthesizer, the MBROLA software, to realtime singing constraints. The work presented in this paper concerns the integration of the MBROLA speech synthesizer into the Max/MSP real-time environment ...

This thesis is concerned with modeling of structural dynamics, dynamic stiffness, and active control of unwanted vibrations in Parallel Kinematic Mechanisms (PKMs) as a result of flexibility of the PKM linkages.
Using energy-based approaches, the structural dynamics of the PKMs with flexible links is derived. Subsequently, a new set of admissible shape functions is proposed for the
flexible links that incorporate the dynamic effects of the adjacent structural components. The resulting mode frequencies obtained from the proposed shape functions are
compared with the resonance frequencies of the entire PKM obtained via Finite Element (FE) analysis for a set of moving platform/payload masses. Next, an FE-based
methodology is presented for the estimation of the configuration-dependent dynamic stiffness of the redundant 6-dof PKMs utilized as 5-axis CNC machine tools at the Tool
Center Point (TCP). The proposed FE model is validated via experimental modal tests conducted on two PKM-based meso-Milling Machine Tool (mMT) prototypes built in the
CIMLab.
For active vibration control of the PKM linkages, a set of PZT transducers are designed, and bonded to the flexible linkage of the PKM to form a “smart link”. An electromechanical model is developed that takes into account the effects of the added
mass and stiffness of the PZT transducers to those of the PKM links. The electromechanical model is subsequently utilized in a controllability analysis where it is shown that the desired controllability of PKMs can be simply achieved by adjusting the
mass of the moving platform. Finally, a new vibration controller based on a modified Integral Resonant Control (IRC) scheme is designed and synthesized with the “smart link” model. Knowing that the structural dynamics of the PKM link undergoes configuration dependent variations within the workspace, the controller must be robust with respect to the plant uncertainties. To this end, the modified IRC approach is shown via a Quantitative Feedback Theory (QFT) methodology to have improved robustness against
plant variations while maintaining its vibration attenuation capability. Using LabVIEW Real-Time module, the active vibration control system is experimentally implemented on
the smart link of the PKM to verify the proposed vibration control methodology.

The progress on fire detection technologies has been substantial over the last decade due to advance in sensor, microelectronics and information technologies, as well as a greater understanding of fire physics. This paper provides a review of progress in fire detection technologies over the last decade, including various emerging sensor technologies (e.g., computer vision system, distributed fiber optic temperature sensor, and intelligent multiple sensor), signal processing and monitoring technology (e.g., realtime control via Internet) and integrated fire detection systems. Some problems and future research efforts related to current fire detection technologies are discussed.

The use of different control applications in automated processes, poses the problem of how to exchange data in Real-Time (RT) between different software platforms. This paper presents a new methodology developed for input and output data exchange between LabVIEW ® and MATLAB ® /Simulink ® , and provides an overview on available methodologies for data exchange comparing their advantages/disadvantages. Finally, a case study is presented in detail where a method based on TCP/IP plus Simulation Interface Toolkit (SIT) is implemented for experimental data exchange between a pilot-scale continuous distillation plant acquisition/control and supervision system carried out using a FieldPoint system from National Instruments (NI) that integrates with LabVIEW ® software and a high level Model Based Predictive Control (MPC) algorithm developed in MATLAB ® /Simulink ® platform.