Abstract
This paper presents new developments in common functional observers for two systems. We improve an existing common functional observer scheme by reducing its order, and then investigate its existence conditions in terms of the original system matrices. These conditions have never been explored and they enable the users to know at the outset the class of systems for which the scheme is applicable. They also show that both observers can be designed independently of each other which significantly simplifies the design process. A numerical simulation verifies the findings.
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Recommended by Associate Editor Young Soo Suh under the direction of Editor PooGyeon Park.
The support from the Fundamental Research Grant Scheme (FRGS) by the Ministry of Education Malaysia (grant no. FRGS/2/2010/TK/MUSM/02/3) is gratefully acknowledged in the work of this paper.
Jiunn Yea Ng graduated with B.Eng. (Hons) in Mechatronics from Monash University in 2009. He joined Monash University Malaysia for postgraduate studies in 2011 under the supervision of A/Prof. Chee Pin Tan. His research focused on observers in control systems. The present study aims to develop common observer schemes for robust state estimation and fault detection and isolation.
Chee Pin Tan received the B.Eng. (first class honors) and Ph.D. degrees from Leicester University, Leicester, UK, in 1998 and 2002, respectively. He was appointed as Lecturer at the School of Engineering, Monash University Sunway campus, Malaysia, in 2002, subsequently promoted to Senior Lecturer in 2008 and is currently an Associate Professor and Deputy Head of School. He has published over 50 internationally peer-reviewed research articles including a book on fault reconstruction. His research interests include robust fault reconstruction and sliding mode observers.
Kok Yew Ng received his B.Eng. (Hons) in Electrical and Computer Systems and Ph.D. in Control System from Monash University, in 2005 and 2009, respectively. He was then subsequently appointed as Lecturer at the School of Engineering, Monash University Malaysia. His research interests include disturbance decoupling fault reconstruction and fault tolerant, sliding mode observer as well as engineering applications using Apple iOS SDK.
Hieu Trinh received his B.Eng. (Hons) in Electrical and Electronic, M.Eng. and Ph.D. from Melbourne University, in 1990, 1992 and 1996, respectively. He was appointed as Lecturer at the School of Engineering of James Cook University and Deakin University, in 1997 and 2001, respectively. He is promoted to Senior Lecturer in 2003 and is currently an Associate Professor in Deakin University. His research focused in complex and intelligent systems. He has made numerous contributions and published papers in key research areas of complex and intelligent systems.
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Ng, J.Y., Tan, C.P., Ng, K.Y. et al. New results in common functional state estimation for two linear systems with unknown inputs. Int. J. Control Autom. Syst. 13, 1538–1543 (2015). https://doi.org/10.1007/s12555-014-0315-x
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DOI: https://doi.org/10.1007/s12555-014-0315-x