Volume 33, Issue 12 pp. 6986-7003
RESEARCH ARTICLE

Singular value decomposition based learning identification for linear time-varying systems: From recursion to iteration

Fazhi Song

Fazhi Song

Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin, China

Key Lab of Ultra-precision Intelligent Instrumentation, Harbin Institute of Technology, Ministry of Industry and Information Technology, Harbin, China

Search for more papers by this author
Li Li

Corresponding Author

Li Li

Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin, China

Key Lab of Ultra-precision Intelligent Instrumentation, Harbin Institute of Technology, Ministry of Industry and Information Technology, Harbin, China

Correspondence Li Li, Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, No. 92, Xidazhi Street, Harbin, China.

Email: [email protected]

Search for more papers by this author
Yang Liu

Yang Liu

Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin, China

Key Lab of Ultra-precision Intelligent Instrumentation, Harbin Institute of Technology, Ministry of Industry and Information Technology, Harbin, China

Search for more papers by this author
Yue Dong

Yue Dong

Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin, China

Key Lab of Ultra-precision Intelligent Instrumentation, Harbin Institute of Technology, Ministry of Industry and Information Technology, Harbin, China

Search for more papers by this author
First published: 26 April 2023

Abstract

System identification is a critical task in various engineering applications such as motion control, signal processing and robotics. In this article, the identification of linear time-varying (LTV) systems that perform tasks repetitively over a finite-time interval is investigated. Traditional LTV system identification typically adopts recursive algorithms in the time domain, which are incapable of tracking drastic-varying parameters and are subject to estimation lag and numerical instability. To address these issues, this article proposes the utilization of an iteration axis in addition to the time axis for estimating repetitive time-varying parameters. Specifically, the proposed approach involves an estimation algorithm for the time-varying parameters based on a recursive least squares (RLS) method along the iteration axis, as well as an update algorithm for the covariance matrix based on singular value decomposition (SVD) to enhance numerical stability. Additionally, a bias compensation method based on noise variance estimation is introduced for the sake of eliminating estimation error induced by measurement noise. Numerical comparisons with existing methods are conducted to demonstrate the effectiveness and superiority of the proposed method.

CONFLICT OF INTEREST STATEMENT

The authors declare that they have no conflict of interest.

DATA AVAILABILITY STATEMENT

Data sharing is not suitable for the article because no datasets are came into being and analyzed during the currently discuss period.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.