0
Research Papers

Cramer–Rao Bound Development for Linear Time Periodic Systems

[+] Author and Article Information
Chris S. Schulz

Department of Aeronautics and Astronautics, Air Force Institute of Technology, WPAFB, OH 45433-7765christopher.schulz@darpa.mil

Donald L. Kunz

Department of Aeronautics and Astronautics, Air Force Institute of Technology, WPAFB, OH 45433-7765donald.kunz@afit.edu

Norman M. Wereley

Department of Aerospace Engineering, University of Maryland, College Park, MD 20742wereley@eng.umd.edu

J. Dyn. Sys., Meas., Control 133(1), 011001 (Nov 23, 2010) (10 pages) doi:10.1115/1.4002104 History: Received June 19, 2008; Revised June 16, 2010; Published November 23, 2010; Online November 23, 2010

System identification techniques are often used to determine the parameters required to define a model of a linear time invariant (LTI) system. The Cramer–Rao bound can be used to validate those parameters in order to ensure that the system model is an accurate representation of the system. Unfortunately, the Cramer–Rao bound is only valid for LTI systems and is not valid for linear time periodic (LTP) systems such as a helicopter rotor in forward flight. This paper describes an extension of the Cramer–Rao bound to LTP systems and demonstrates the methodology for a simple LTP system.

FIGURES IN THIS ARTICLE
<>
Copyright © 2011 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Comparison of parameter estimates for LTI and LTP systems (10)

Grahic Jump Location
Figure 2

Example of Cramer–Rao bounds for parameter estimates (11)

Grahic Jump Location
Figure 3

Example of a simple LTP system represented by a modulating gain (15)

Grahic Jump Location
Figure 4

Multiharmonic response of a LTP system (16)

Grahic Jump Location
Figure 5

Rigid rotor blade flapping moments (17)

Grahic Jump Location
Figure 6

Cramer–Rao bounds for all frequency and noise values

Grahic Jump Location
Figure 7

Blade flap frequency response for the fundamental frequency band input (10)

Grahic Jump Location
Figure 8

Cramer–Rao bounds for 100 runs at all frequencies (Sv=4)

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In