Semiactive control of a shear building using an adaptive observer

This paper illustrates the design and use of an adaptive observer in a semiactive control scheme for a building with a magneto-rheological damper. The adaptive observer allows to estimate variables that are difficult to measure in a real structure, but still required by some state-feedback controllers. The aim of this work is to exemplify the use of a recently developed adaptive observer that permits the reconstruction of signals and parameters that correspond directly to physical variables, in contrast to other adaptive observers that require canonical forms and state transformation that lead to states and parameters with no physical meaning. A controller derived from a singular perturbation analysis is utilized in numerical simulation to attenuate the response of a building subject to seismic excitation. The controller´s parameters are also estimated via the modified LuGre model for magneto-rheological dampers. Sufficient conditions to guarantee asymptotic stability are given in terms of a gain matrix.