Seminar by Professor Anna Soffía Haukstóttir

Professor Anna Soffía Hauksdóttir from the University of Iceland gives a seminar on “Closed Form and Taylor Form Expressions for Computation of Response to Linear Time Invariant State Equations”.

 

Location: Building 326, Room 124, Technical University of Denmark (Lyngby Campus)

Time: Thursday May 16, 2024: 13:00-14:00

 

Everybody is welcome.

 

Closed Form and Taylor Form Expressions for Computation of Responses to Linear Time Invariant State Equations

Prof. Anna Soffía Hauksdóttir, University of Iceland

 

Abstract:

Closed form expressions are derived for MIMO responses to impulse, step, ramp and higher order monomial inputs as well as sinusoidal inputs. They can be evaluated directly for any time t.  Step wise procedures are also derived for inputs that are asynchronous steps and approximations to general inputs by piecewise constant, linear and quadratic interpolation. All these results depend on the vector eAtb, its antiderivatives and derivatives. The closed forms involve roots and coefficients of the characteristic equation of the system matrix A and are in a form readily implemented by standard available software. They tend to become unstable for medium sized systems, but the accuracy is largely independent of t. It should be emphasized here though, that for smaller to medium sized systems, the closed forms are very important in order to shed light on the physical properties and to ease analysis of the system solution, as well as being useful for their response computation. In addition, the need for using a Laplace transformation to find system solutions on a case-by-case basis is eliminated.The closed form expressions are in all cases complemented with expressions based on Taylor series approximations also readily implemented by standard available software. By contrast the accuracy of these Taylor expressions depend on the size of the norm of At and can be used to obtain accurate results for much larger systems, restricting the value of t if necessary by employing a standard stepping procedure.

 

Biography:

Anna Soffía Hauksdóttir graduated from the University of Iceland with a CS degree in Electrical Engineering in 1981. She completed her MS and PhD degrees from The Ohio State University majoring in control systems in 1983 and 1987 respectively. She received the “Centennial Keys to the Future Award” from the Institute of Electrical and Electronics Engineers (IEEE), Vehicular Technology Society in 1984. She has been a professor at the Electrical and Computer Engineering Department of the University of Iceland since 1989. She received the Knights Cross of the Icelandic Order of the Falcon for electrical engineering research achievements in 1998 and the gold medal of the Icelandic Society of Chartered Engineers for contributions to control applications in 2001. Anna Soffía received the Teaching award from the School of Engineering and Science at the University of Iceland in 2021, nominated by her students.

Tidspunkt

tor 16 maj 24
13:00 - 14:00

Arrangør

DTU Compute

Hvor

DTU Building 326, Room 124