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Utvärdering av latens och jitter för LQG och PID

Zaben, Haitham (2007) In MSc Theses
Department of Automatic Control
Abstract
Digital control theory normally assumes equidistant sampling intervals and a negligible or constant control delay from sampling to actuation, so called input/output latency. However this can seldom be achieved in practice. In the computer tasks interfere with each other through preemption and blocking when waiting for common resources. The execution time for each task may be data-dependant and therefore differ from one sample to another, which introduces a so called jitter in the latency. The latency and jitter introduced by the computer can lead to significant performance degradation, and may also lead to instability. This thesis discusses how computer-induced latency and jitter affects computer-controlled systems. Control systems, with... (More)
Digital control theory normally assumes equidistant sampling intervals and a negligible or constant control delay from sampling to actuation, so called input/output latency. However this can seldom be achieved in practice. In the computer tasks interfere with each other through preemption and blocking when waiting for common resources. The execution time for each task may be data-dependant and therefore differ from one sample to another, which introduces a so called jitter in the latency. The latency and jitter introduced by the computer can lead to significant performance degradation, and may also lead to instability. This thesis discusses how computer-induced latency and jitter affects computer-controlled systems. Control systems, with various processes and control structure of either PID or LQG, are analyzed under various latency and jitter conditions. The systems are analyzed and simulated with the Matlab-based tools Jitterbug and TrueTime. Jitterbug allows the computation of a cost function for linear systems under various timing conditions. With this tool, one can estimate how sensitive a control system is to latency and jitter. With TrueTime the user can simulate a control system in a real-time kernel under various timing conditions. The results from the analysis and the simulations are presented and discussed. (Less)
Please use this url to cite or link to this publication:
author
Zaben, Haitham
supervisor
organization
year
type
H3 - Professional qualifications (4 Years - )
subject
publication/series
MSc Theses
report number
TFRT-5807
ISSN
0280-5316
language
Swedish
id
8847769
date added to LUP
2016-03-17 13:04:28
date last changed
2016-03-17 13:04:28
@misc{8847769,
  abstract     = {{Digital control theory normally assumes equidistant sampling intervals and a negligible or constant control delay from sampling to actuation, so called input/output latency. However this can seldom be achieved in practice. In the computer tasks interfere with each other through preemption and blocking when waiting for common resources. The execution time for each task may be data-dependant and therefore differ from one sample to another, which introduces a so called jitter in the latency. The latency and jitter introduced by the computer can lead to significant performance degradation, and may also lead to instability. This thesis discusses how computer-induced latency and jitter affects computer-controlled systems. Control systems, with various processes and control structure of either PID or LQG, are analyzed under various latency and jitter conditions. The systems are analyzed and simulated with the Matlab-based tools Jitterbug and TrueTime. Jitterbug allows the computation of a cost function for linear systems under various timing conditions. With this tool, one can estimate how sensitive a control system is to latency and jitter. With TrueTime the user can simulate a control system in a real-time kernel under various timing conditions. The results from the analysis and the simulations are presented and discussed.}},
  author       = {{Zaben, Haitham}},
  issn         = {{0280-5316}},
  language     = {{swe}},
  note         = {{Student Paper}},
  series       = {{MSc Theses}},
  title        = {{Utvärdering av latens och jitter för LQG och PID}},
  year         = {{2007}},
}