Comparison of low-complexity controllers in varying time-delay systems

Abstract : Motivated by the recent developments in networked control systems and control over wireless, this paper presents a comparison of five control algorithms that are based on PID, IMC and fuzzy gain scheduling techniques and discusses their performance in varying time-delay systems. The low complexity of the proposed algorithms makes their use attractive in resource-constrained environments such as wireless sensor and actuator networks. The control system consists of a controller, a simple process and an output delay in the feedback loop. Three different delay models are considered in this framework; constant, random, and correlated random delay. In addition to presenting modifications to the control algorithms to better fit the varying time-delay systems a delay-robust tuning method is proposed, and the performance of various controllers is evaluated using simulation. The results show the benefits of adapting the controller parameters based on delay measurement if its amplitude is significant with respect to the time-constant of the process. Nevertheless, the PID algorithm used in the study also performs well in all scenarios, and this is achieved by its careful tuning

Localization Services for Online Common Operational Picture and Situation Awareness

Many operations, be they military, police, rescue, or other field operations, require localization services and online situation awareness to make them effective. Questions such as how many people are inside a building and their locations are essential. In this paper, an online localization and situation awareness system is presented, called Mobile Urban Situation Awareness System (MUSAS), for gathering and maintaining localization information, to form a common operational picture. The MUSAS provides multiple localization services, as well as visualization of other sensor data, in a common frame of reference. The information and common operational picture of the system is conveyed to all parties involved in the operation, the field team, and people in the command post. In this paper, a general system architecture for enabling localization based situation awareness is designed and the MUSAS system solution is presented. The developed subsystem components and forming of the common operational picture are summarized, and the future potential of the system for various scenarios is discussed. In the demonstration, the MUSAS is deployed to an unknown building, in an ad hoc fashion, to provide situation awareness in an urban indoor military operation.Peer reviewe

Multimedia Applications in Industrial Automation - Collected papers of the Spring 1997 postgraduate seminar

Introduction Heikki Hyotyniemi Helsinki University of Technology, Control Engineering Laboratory Otakaari 5 A, FIN-02150 Espoo, Finland 1.1 About the course Usually, the post-graduate courses in control engineering concentrate on established, more or less traditional areas of control engineering. This year, however, the course differs from the traditional --- there is no ready-to-adopt pre-processed material. The course is more like research in the unknown area. Only after some years the turmoil in the field of Internet can be seen in a perspective --- but then it is too late. Now, it is the time to react to the challenges. Internet will certainly have great impact in engineering work, control and automation engineering being no exception. As in all of the computer oriented disciplines, working with Internet is largely concentrated on software production, user interface polishing and other more or less mechanical tasks. The truth is that code crunching and hac