title: On the identification of Hammerstein systems with time-varying parameters.
abstract: A growing emphasis on the analysis of time-varying systems has intensified the need for simpler and more efficient identification methods for these systems. In this contribution, we examine the time-varying Hammerstein structure, comprising a memoryless nonlinearity with time-varying parameters followed by a time-varying linear filter. Two existing approaches for the identification of these systems, ensemble approaches and basis expansion methods, are combined as a single algorithm to give a much improved estimation tool. The proposed algorithm, applied to data from a simulation of a time-varying Hammerstein system, is used to construct models of the reflex contribution to joint stiffness and the results obtained are compared to those using the basis expansion method alone.
authors.affiliation: Department of Electrical and Computer Engineering, Schulich School of Engineering, University of Calgary, 2500 University Dr. NW, Calgary, Alberta, T2N 1N4, Canada.
authors.forename: Bashiru I
authors.initials: BI
authors.lastname: Ikharia
authors.forename: David T
authors.initials: DT
authors.lastname: Westwick
mesh_terms: D000465:Algorithms; D000843:Ankle Joint / Q000502:physiology; D008954:Models, Biological; D012018:Reflex; D019415:Torque