Search for dissertations about: "Henrik Sandberg"

Showing result 1 - 5 of 27 swedish dissertations containing the words Henrik Sandberg.

  1. 1. Compensating for Unreliable Communication Links in Networked Control Systems

    Author : Erik Henriksson; Karl Henrik Johansson; Henrik Sandberg; Bruno Sinopoli; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; networked control; packet loss compensation; unreliable communication; control over wirless networks; Automatic control; Reglerteknik;

    Abstract : Control systems utilizing wireless sensor and actuator networks can be severely affectedby the properties of the communication links. Radio fading and interferencemay cause communication losses and outages in situations when the radio environmentis noisy and low transmission power is desirable. READ MORE

  2. 2. Contention-based Multiple Access Architectures for Networked Control Systems

    Author : Chithrupa Ramesh; Karl Henrik Johansson; Henrik Sandberg; Dawn Tilbury; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Elektroteknik;

    Abstract : Networked Control Systems (NCSs) use a wireless network for communication between sensors and controllers, and require a Medium Access Controller (MAC) to arbitrate access to the shared medium. Traditionally, a MAC for control systems is chosen primarily based on the delay it introduces in the closed loop. READ MORE

  3. 3. State-based Channel Access for a Network of Control Systems

    Author : Chithrupa Ramesh; Karl Henrik Johansson; Henrik Sandberg; Joao Hespanha; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; networked control; multiple access; event-based; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Wireless networked control systems use shared wireless links to communicate between sensors and controllers, and require a channel access policy to arbitrate access to the links. Existing multiple access protocols perform this role in an agnostic manner, by remaining insular to the applications that run over the network. READ MORE

  4. 4. Linear Time-Varying Systems: Modeling and Reduction

    Author : Henrik Sandberg; Anders Rantzer; Alexandre Megretski; Institutionen för reglerteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; linear time-varying; model reduction; balanced truncation; error bounds; power converters; harmonics; periodic modeling; inverter locomotive; linear time-varying; model reduction; balanced truncation; error bounds; power converters; periodic modeling; harmonics; inverter locomotive;

    Abstract : Linear time-invariant models are widely used in the control community. They often serve as approximations of nonlinear systems. For control purposes linear approximations are often good enough since feedback control systems are inherently robust to model errors. In this thesis some of the possibilities for linear time-varying modeling are studied. READ MORE

  5. 5. Model Reduction for Linear Time-Varying Systems

    Author : Henrik Sandberg; Anders Rantzer; Sanjay Lall; Institutionen för reglerteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Automation; robotics; control engineering; Performance limitations; Convergence analysis; Frequency-domain analysis; Error bounds; Time-varying systems; Model reduction; Linear systems; Automatiska system; robotteknik; reglerteknik; Model reduction;

    Abstract : The thesis treats model reduction for linear time-varying systems. Time-varying models appear in many fields, including power systems, chemical engineering, aeronautics, and computational science. They can also be used for approximation of time-invariant nonlinear models. Model reduction is a topic that deals with simplification of complex models. READ MORE