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Despite availability of multiple orthogonal communication channels on common sensor network platforms, such as MicaZ motes, and despite multiple simulation-supported designs of multi-channel MAC protocols, most existing sensor networks use only one channel for communication, which is a source of bandwidth inefficiency. In this work, we design, implement,(More)
Co-simulation of controller task execution, network transmissions, and continuous plant dynamics. Accomplished by providing models of real-time kernels and networks as Simulink blocks User code in the form of tasks and interrupt handlers is modeled by MATLAB or C-code Investigate the true, timely behaviour of time or event-triggered control loops, subject(More)
Most currently deployed sensor networks use the same channel to communicate information among nodes. This is a source of great inefficiency as it poorly utilizes the available wireless spectrum. This paper takes advantage of radio capabilities of MicaZ motes that can communicate on multiple frequencies as specified in the 802.15.4 standard. We consider the(More)
1. Background The use of control-based methods for resource management in real-time computing and communication systems has gained a substantial interest recently. Applications areas include performance control of web-servers, dynamic resource management in embedded systems, traffic control in communication networks, transaction management in database(More)
This paper introduces the area of Cyber-Physical Systems (CPS) and describes the relation to Modeli-ca and Modelica-based tools. Special aspects of CPS applications that should make Modelica well suited for their modeling and simulation are highlighted. Recent Modelica developments facilitating integrated model-based system development applicable to CPS are(More)
The paper presents two recently developed, MATLAB-based analysis tools for real-time control systems. The first tool, called JITTERBUG, is used to compute a performance criterion for a control loop under various timing conditions. The tool makes it easy to quickly judge how sensitive a controller is to implementation effects such as slow sampling, delays,(More)
The manual describes the use of TrueTime, a Matlab/Simulink-based tool for simulation of distributed real-time control systems. The tool facilitates detailed co-simulation of plant dynamics, controller task execution, and network transmissions. The TrueTime Kernel and TrueTime Network blocks are described, and the real-time kernel primitives are detailed.
The article presents two MATLAB-based tools for analysis and simulation of real-time control systems: JITTERBUG and TRUETIME. JITTERBUG allows the user to compute a quadratic performance criterion for a linear control system under various timing conditions. The control system is described using a number of continuous-and discrete-time linear systems. A(More)
The main goal of this project was to use the Modelica features on embedded systems, real-time systems and basic mechanical modeling for the control of a two-wheeled self-balancing personal vehicle. The Elektor Wheelie, a Segway-like vehicle, was selected as the process to control. Modelica is an object-oriented language aimed at modeling of complex systems.(More)
The paper presents some preliminary results on dynamic scheduling of model predictive controllers (MPC's). In model predictive control, the control signal is obtained by optimization of a cost function in each sample, and the MPC task may experience very large variations in execution time. Unique to this application, the cost function also offers an(More)