| 1. |
- Gumussoy, Suat, et al.
(författare)
-
Improving Linear State-Space Models with Additional Iterations
- 2018
-
Ingår i: IFAC-PapersOnLine. - : Elsevier BV. - 2405-8963. ; 51:15, s. 341-346
-
Konferensbidrag (refereegranskat)abstract
- An estimated state-space model can possibly be improved by further iterations with estimation data. This contribution specifically studies if models obtained by subspace estimation can be improved by subsequent re-estimation of the B, C, and D matrices (which involves linear estimation problems). Several tests are performed, which show that it is generally advisable to do such further re-estimation steps using the maximum likelihood criterion. Stated more succinctly in terms of MATLAB® functions, ssest generally outperforms n4sid.
|
|
| 2. |
- Khorsand Vakilzadeh, Majid, 1984, et al.
(författare)
-
Experiment design for improved frequency domain subspace system identification of continuous-time systems
- 2015
-
Ingår i: IFAC-PapersOnLine. - : Elsevier BV. - 2405-8963. ; 48:28, s. 886-891
-
Konferensbidrag (refereegranskat)abstract
- A widely used approach for identification of linear, time-invariant, MIMO (multi-input/multi output) systems from continuous-time frequency response data is to solve it in discrete-time domain using subspace based identification algorithm incorporated with a bilinear transformation. However, the bilinear transformation maps the distribution of the frequency lines from continuous-time domain to discrete-time domain in a non-linear fashion which may make identification algorithm to be ill-conditioned. In this paper we propose a solution to get around this problem by designing a dedicated frequency sampling strategy. Promising results are obtained when the algorithm is applied to synthetic data from a 6DOF mass-spring model.
|
|
| 3. |
- McKelvey, Tomas, 1966-, et al.
(författare)
-
Efficient Construction of Transfer Functions from Frequency Response Data
- 1994
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In this paper, we present a novel non-iterative algorithm to identify linear time-invariant systems from frequency response data. The algorithm is related to the recent time-domain subspace identification techniques. Promising results are obtained when the algorithm is applied to the real frequency data originating from a large flexible structure. A robustness analysis is performed and under weak conditions on the measurement noise, it is shown that the algorithm is consistent.
|
|
| 4. |
- McKelvey, Tomas, 1966-, et al.
(författare)
-
Vibration Data Analysis for a Commercial Aircraft
- 1995
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Using data from extensive vibrational tests of the new Saab 2000 aircraft, a combined method for vibration analysis is studied. The method is based on a realization algorithm followed by standard prediction error methods (PEM). We find that the realization algorithm gives good initial model parameter estimates that can be further improved by the use of PEM. We use the method to get insights into the vibrational eigenmodes.
|
|
